Live Updates: Israel Conducts New Strikes on Tehran and Trump Calls for Iran’s ‘Unconditional Surrender’

Fears of a wider war are growing among American officials as Israel presses the White House to intervene in its conflict with Iran. If the United States joins the Israeli campaign and strikes Fordo, a key Iranian nuclear facility, the Iranian-backed Houthi militia will almost certainly resume striking ships in the Red Sea, the officials said. They added that pro-Iranian militias in Iraq and Syria would probably try to attack U.S. bases there.

Other officials said that in the event of an attack, Iran could begin to mine the Strait of Hormuz, a tactic meant to pin American warships in the Persian Gulf.

Commanders put American troops on high alert at military bases throughout the region, including in the United Arab Emirates, Jordan and Saudi Arabia. The United States has more than 40,000 troops deployed in the Middle East.

Two Iranian officials have acknowledged that the country would attack U.S. bases in the Middle East, starting with those in Iraq, if the United States joined Israel’s war.

Iran would also target any American bases that are in Arab countries and take part in an attack, the two officials said.

“Our enemies should know that they cannot reach a solution with military attacks on us and will not be able to force their will on the Iranian people,” Iran’s foreign minister, Abbas Araghchi, said in a statement on Monday. Mr. Araghchi told his European counterparts in phone conversations that if the war spread, the blame would be on Israel and its main supporters, according to a summary of the calls provided by Iran’s foreign ministry.

U.S. officials said Iran would not need much preparation to attack American bases in the region. The Iranian military has missile bases within easy striking range of Bahrain, Qatar and United Arab Emirates.

The prospect of U.S. forces joining the war has increased in recent days as Israel has continued its campaign, and Iran has launched waves of missiles at Israel in response.

It is not clear how much damage a strike on Fordo would do to Iran’s nuclear capabilities or how long it would delay the development of a weapon. Iran’s current stockpile of enriched uranium is also hidden in tunnels at different locations in the country.

Several American officials said that Israel would need U.S. help to more significantly damage Iran’s nuclear program.

American assistance could include providing air cover for Israeli commandoes who go into Iran on the ground. But, officials said, the more probable outcome is a strike by U.S. B-2 stealth bombers armed with the Massive Ordnance Penetrator, a weapon that theoretically has the ability to bore into the mountain that shelters the underground Fordo facility.

Any strike on Fordo by the United States or with U.S. assistance would prompt Iran and its allies to retaliate.

Iran and its allies have been able to harm Americans in the past. The Houthis curbed their attacks after the Trump administration stepped up strikes on them. But in recent years they have repeatedly tried to strike American warships and have hit commercial shipping. In January 2024, an Iranian-backed militia carried out a drone attack on a U.S. base in Jordan near the Syrian border that killed three American soldiers.

American intelligence agencies have long concluded that Iran was close to being able to make a nuclear weapon but had not decided whether to do so. If Iran decided to make a weapon, it would be less than a year away from being able to field one. A crude, more basic nuclear bomb could possibly be constructed more quickly.

President Trump has repeatedly said he will not allow Iran to obtain a nuclear weapon. On Tuesday, he called for Iran’s unconditional surrender.

But the Israeli attacks may have changed Iran’s calculus. U.S. officials skeptical of Israel’s campaign said on Tuesday that it has probably convinced Tehran that the only way to prevent future attacks would be to develop a full nuclear deterrent.

Some of those officials said that if Iran is likely to pursue a nuclear weapon no matter what, pressure could increase on the Trump administration to strike.

But critics of aggressive, militaristic foreign policy said it was not too late for the United States to turn back.

“It is never too late not to start a war,” said Rosemary Kelanic, the director of the Middle East program at Defense Priorities, a think tank that advocates a restrained foreign policy.

Ms. Kelanic acknowledged that Israel’s strike had given Iran an incentive to potentially develop a nuclear weapon. But she added that the incentive would “multiply dramatically if the United States joins the war.”

“Once you get involved, man, it’s really hard to step back,” she said. “You are just going to go all in.”

Adam Goldman contributed reporting.

Senator Tim Kaine, Democrat of Virginia, on Monday introduced a similar resolution.

Both efforts face long odds on Capitol Hill given Republicans’ reluctance to challenge Mr. Trump’s power, but with some lawmakers in both parties openly resisting further U.S. involvement, they are likely to prompt a vibrant debate. The measures enjoy a special status that will compel Congress to vote on them one way or the other in the coming days.

Still, Speaker Mike Johnson has, so far, been successful in deflecting efforts to force Republican members to take any vote that would require them to challenge Mr. Trump’s authority, and he could seek a procedural solution that would allow him to circumvent a vote on a war declaration.

The move in the House quickly drew detractors, including Representative Mike Lawler, Republican of New York, who posted on social media that “If AOC and Massie are a yes, that’s a good bet that I’ll be a no.” He was referring to Representative Alexandria Ocasio-Cortez of New York, who was among the Democrats backing the measure.

And in the Senate, defense hawks cheered Mr. Trump’s bellicose posture.

Senator Lindsey Graham, Republican of South Carolina, on Tuesday reiterated his stance that he supports U.S. involvement in the conflict against Iran.

“Yeah, I want us to go all in to help Israel destroy their nuclear programs,” he said, adding that he had spoken to Mr. Trump Monday evening about his views.

When asked what role Congress should have in authorizing offensive strikes in Iran, Senator Bernie Moreno, Republican of Ohio, deferred to Mr. Trump.

“I have total faith and confidence in the president of the United States,” he said in an interview on Tuesday.

While Congress has not issued a formal declaration of war since World War II, it has authorized the use of military force through a series of resolutions, most notably following the Sept. 11, 2001, attacks.

That resolution granted President George W. Bush the authority to use military force against those responsible for the attacks and any groups that harbored them. The following year, Congress passed another resolution authorizing the use of force against Iraq, citing concerns about weapons of mass destruction.

The pair of authorizations has been used to justify a wide range of military actions since then, including the Obama administration’s campaign against ISIS in 2014. In recent years, lawmakers from both parties have criticized the broad scope of these measures, arguing that they give the executive branch too much power over decisions that should rest with Congress.

More recently, the debate over the scope of presidential war powers was reignited during Mr. Trump’s first term after the killing of Gen. Qassim Soleimani of Iran. The administration shifted its legal rationale multiple times, initially citing the 2002 authorization as basis for the argument that Iran, and General Soleimani, posed “imminent threats” before later contradicting that position in a report to Congress.

A 2023 effort to repeal the authorizations used to justify the strike, led by Mr. Kaine, stalled after being sent to the House but drew bipartisan support in the Senate, including from then-Senator JD Vance of Ohio.

A day later, President Trump on Tuesday wrote on social media, “we know exactly where” the ayatollah is. But he added that “we are not going to take him out (kill!), at least for now.”

He added, “Our patience is growing thin.”

Here is a closer look at Ayatollah Khamenei, his rise to power and his role in the deepening confrontation with Israel.

From revolutionary aide to supreme leader

Born in 1939 into a religious family of modest means in Mashhad, a pilgrimage city in eastern Iran, Mr. Khamenei came of age in the years leading up to the 1979 revolution that overthrew the shah.

He was imprisoned repeatedly by the security services of the U.S.-backed autocrat Mohammed Reza Pahlavi, and he rose through the ranks of the religious opposition as a close ally of Ayatollah Ruhollah Khomeini, who led the revolution and founded the Islamic Republic of Iran.

Mr. Khamenei quickly emerged as one of the most trusted lieutenants in the new Iranian regime, and he was president for much of the 1980s.

When Ayatollah Khomeini died in 1989, Mr. Khamenei, by that time an ayatollah himself, was elevated to Iran’s supreme leader. He set about consolidating control of the country’s political, military and security apparatus, and cracking down on dissent to shore up his position as the ultimate decision maker.

Absolute power under Iran’s theocratic system

As Iran’s supreme leader, Ayatollah Khamenei sits above all other branches of government. He appoints the heads of the judiciary, state media and key security agencies, and he holds final authority over who can run for president.

Ayatollah Khamenei also controls foreign and military policy, overseeing the Revolutionary Guards Corps, which defends Iran’s Islamic system and sits apart from the rest of the military, and the powerful Quds Force, which directs Iran’s foreign operations across the Middle East.

His authority extends to the nuclear program, placing him at the center of Iran’s escalating confrontation with Israel.

An architect of Iran’s regional strategy

For decades, Ayatollah Khamenei has been at the heart of Iran’s hard-line foreign policy, positioning the country as a counterweight to American, Israeli and Saudi influence across the Middle East. Under his leadership, Iran has trained, armed and funded a network of proxy forces stretching from Lebanon to Yemen, allowing Tehran to project power and confront its rivals without provoking a war on Iranian soil.

But that strategy unraveled on Friday, when Israel launched its largest-ever attack against Iran, targeting military and nuclear sites and killing an array of senior officials.

Israel said the military campaign was an effort to prevent Tehran from acquiring nuclear weapons. Iranian officials have publicly said that their country’s nuclear program is intended for civilian uses only and have denied that it is building a bomb; Ayatollah Khamenei issued a religious ruling, or fatwa, in 2003 declaring nuclear weapons forbidden under Islam. But Israel and Western governments have long accused Tehran of seeking the capability to build a bomb if it so chooses.

Under guard, and under threat

Ayatollah Khamenei’s movements are tightly controlled and his whereabouts rarely disclosed. His personal security is overseen by an elite Revolutionary Guards unit that reports directly to his office, according to analysts.

He was reportedly moved last week to a secret location where he could remain in contact with the military. That follows similar reports last year, when the ayatollah was also moved to a safe location a day after the assassination of Hassan Nasrallah, who led the Lebanese militant group Hezbollah and was a longtime ally.

In recent days, Israel has killed a number of senior officials in Iran, including the country’s top military commanders and nuclear scientists.

But a direct attack on Ayatollah Khamenei himself would represent an extraordinary escalation of the current conflict. Such a move could have unpredictable and far-reaching consequences across the Middle East.

In the first days of the war, Iran fired as many as almost 100 missiles in a single night, in salvos of dozens. But overnight into Tuesday, fewer than 30 projectiles breached Israeli airspace. An early morning salvo included just a few missiles — far fewer than in previous waves — according to Lt. Col. Nadav Shoshani, an Israeli military spokesperson.

Since the fighting began on Friday, there have been more than 35 direct hits on Israeli military facilities, a research university, an oil refinery and residential areas. The Iranian missiles have killed at least 24 people, injured hundreds and left over 2,000 people homeless, according to the Israeli Prime Minister Office. Israel successfully intercepts most incoming missiles with its advanced air defense systems, and is trying to strip Iran of its ability to launch missiles by targeting its launchers and stockpiles. Brig. Gen. Effie Defrin, the military’s chief spokesperson, said that the Israeli air force had destroyed more than 120 surface-to-surface launchers, which he said was about one-third of Iran’s arsenal.

The slowdown in Iran’s missile fire may indicate that Israeli strikes have significantly damaged Tehran’s ability to launch projectiles. But it could also suggest that Iranian leaders are preparing for a conflict that may stretch on for weeks or even months.

Israel initially estimated that Iran had around 2,000 ballistic missiles before the war began. After firing roughly 400 and sustaining hits to some of its stockpiles, Israeli experts and officials now believe Iran still has over 1,000 ballistic missiles.

“Iran cannot sustain a pace of hundreds of missiles per night for very long — they’ll run out of stock,” said Raz Zimmt, director of the Iran and Shiite Axis research program at the Institute for National Security Studies, an Israeli think tank. “But if they spread it out, they can drag Israel into a war of attrition.”

Iran at first attempted to overwhelm Israel’s defense systems by launching large volleys of missiles simultaneously. But as its ability to fire massive barrages diminishes, Israel’s interception capabilities become more effective. This is critical, because ballistic missiles are Tehran’s primary offensive tool against Israel and crucial to its ability to retaliate.

Despite the Israeli defenses, some missiles appear to have struck on Tuesday. Videos verified by The New York Times show several explosions close to key Israeli military sites near the town of Ramat Hasharon, north of Tel Aviv.

While Iran’s armed forces are among the largest in the Middle East, with at least 580,000 active-duty personnel, their ability to reach Israel — over 600 miles away — is limited by an outdated air force. Iranian-backed militias that sometimes act as proxies in attacking Israel, such as Hezbollah in Lebanon and Hamas in Gaza, have been significantly weakened over the past two years and cannot provide meaningful support.

Even so, Israel remains concerned that Iran may still find new ways to fight back.

For days, Iranians have described worsening problems as they tried to contact loved ones, get reliable news, access their bank accounts online or simply connect to the internet. The restrictions may also be affecting people’s ability to see warnings related to the war, like one the Israeli military made on Monday, when it told people in part of Tehran to evacuate because of an imminent strike.

Netblocks, an internet monitoring group, reported on Tuesday that an “analysis of telemetry shows a significant reduction in internet traffic” in Iran, showing a graphic with a steep decline.

“It seems like we’re headed toward a full disconnection,” said Amir Rashidi, a cybersecurity expert based in the United States.

Several Iranians around the country said in interviews that mobile data networks were down in parts of Iran, making it impossible for many people to access foreign mobile apps and websites on their phones — only domestic sites and apps remained active. They reported that the virtual private networks, or V.P.N.s, that Iranians use to access the internet free of restrictions were being blocked intermittently.

“They disconnected WhatsApp; then they connected it; then they disconnected it again,” said Arta, a 28-year-old from Tehran, via text. “When you’re on cellular, V.P.N. connects in some places and not in others. They’ve closed most of the ports.”

The government has urged people to use the N.I.N., which allows people to message only using government platforms — software that many people don’t trust or believe to be secure.

For decades, the Iranian government has restricted access to certain websites and social media applications, such as Facebook or Instagram, and many Iranians have relied on a collection of V.P.N.s to bypass the government’s filters.

But since Israel began attacking Iran last week, many people have said that their V.P.N. services were failing, forcing them to have to search for working ones or to try “hopping” from one network to another.

The disruptions so far do not appear to be uniform, though many believe that the government is trying to prevent people from sharing information about where Israel has struck, including sharing photos or videos.

There also appears to be intense security around such strikes, making it difficult to assess the damage and civilian toll. In some videos that have been shared, people can be heard asking others “not to film” and “not to block the way” for emergency services.

In the absence of reliable information, some Iranians have described a sense of panic, with people sharing tips about what GPS and messaging apps to use if the government restricts the internet entirely, save for the N.I.N. “Google Play isn’t showing routes correctly,” Mr. Rashidi said, “so some people who were trying to evacuate are now lost.”

The Iranian authorities have warned people against using apps like WhatsApp, saying that the country is under cyberattack from Israel.

Leily Nikounazar contributed reporting.

Many of the Iranians interviewed, all of whom asked to be identified only by their first names because of the sensitivity of the situation, are struggling to absorb their new, ever-changing reality.

Crowds of Iranians have fled Tehran since Israel launched an attack on Friday. Evacuations have intensified in the hours since the Israeli military issued an evacuation order for a large part of northeastern Tehran, saying it planned to target “military infrastructure” in the area.

Some gas stations have reportedly closed because they ran out of fuel, and social media footage verified by The New York Times showed traffic clogging roads leading out of Tehran.

Israel’s attacks have killed more than 224 people and injured more than 1,800 people in Iran, according to the country’s health ministry. Iranian strikes have killed more than 24 people and injured more than 600 in Israel, according to the Israeli government.

“Before this conflict erupted, we used to joke in group chats and online that the next disaster would be something absurd like a volcanic eruption, an alien invasion or a zombie attack,” Kimia said. “What we didn’t think about was another war.”

She has been glued to the news, and she said her life has become a maelstrom of stress, worry and uncertainty.

“It felt like all of Tehran was evacuating,” said Fahimeh, the jewelry designer from Tehran. Fuel lines were so long that she skipped refueling, and while she did not notice a grocery shortage, she was only allowed to buy two cans of tuna.

“Drivers were aggressively overtaking each other, showing little patience or empathy,” Fahimeh said. “People seemed frustrated and anxious. My foot was constantly on the clutch and brake.”

Leili, a teacher who lives in the province of Mazandaran, said many Iranians were starting to seek refuge in her area.

Grocery shortages there were becoming increasingly noticeable, she said, and meat and chicken were becoming hard to find.

“Cooking oil is now scarce in stores, and if this continues, the situation could grow more concerning,” she said. While she hasn’t stockpiled supplies, Leili said, “many others have begun hoarding, likely driven by memories of shortages during the Iran-Iraq war and fears of future scarcity.”

Many Iranians are experiencing a mix of emotions, a concern for their homeland and its future, alongside satisfaction at the regime’s humiliation, Leili added. There are questions about what the war will mean for the nation’s political future, too.

If the regime was overthrown, Masoud wondered, would the United States intervene to set up a new Western-style secular democracy, as he and others he knew hoped? Or would Israel and the United States “destroy the regime and then abandon Iran to its fate,” as Masoud said most people he spoke to feared?

“People are terrified of the uncertain fate that awaits them. Like walking in the dark, when you can’t see ahead, you are most afraid,” Masoud said.

Both Iran and Israel have ignored possible routes toward de-escalation. And on Tuesday morning, President Trump said he wanted something “better than a cease-fire,” adding he wanted a “complete give-up” by Iran.

“The small routines and plans I had for my life are shattered,” Kimia said. “I can no longer envision a future beyond ensuring the safety of my loved ones and bracing for the worst if something happens to them.”

“From an official diplomatic posture perspective, the Israelis will not confirm or deny” their nuclear arsenal, said Alexander K. Bollfrass, a nuclear security expert at the International Institute for Strategic Studies in London.

Instead, Israel has said it will not be the first country to “introduce” nuclear weapons to the Middle East. That deliberately vague wording amounts to what Mr. Bollfrass called an “obfuscation over what is clearly an established nuclear weapons program.”

How big is Israel’s nuclear arsenal?

Israel is widely believed to have at least 90 warheads and enough fissile material to produce up to hundreds more, according to the Center for Arms Control and Nonproliferation and the Nuclear Threat Initiative.

The International Atomic Energy Agency, the nuclear watchdog for the United Nations, has assessed that 30 countries are capable of developing nuclear weapons but only nine are known to possess them. Israel has the second-smallest arsenal among the nine, ahead only of North Korea, according to a Nobel Prize-winning advocacy group, the International Campaign to Abolish Nuclear Weapons. Israel could fire warheads from fighter jets, submarines or ballistic missile ground launchers, experts said.

Israel is one of five countries — joining India, Pakistan, North Korea and South Sudan — that is not a signatory to the U.N. Nuclear Nonproliferation Treaty. The agreement, which came into force in 1970, generally commits governments to promoting peaceful uses of nuclear energy and preventing the spread of nuclear weapons.

(Iran is a signatory to the treaty, although Israel and world powers have accused Tehran of violating it by unnecessarily enriching uranium at high enough levels to build a nuclear weapon.)

Israel would have to give up its nuclear weapons to sign the treaty, which recognizes only five countries as official nuclear states: Britain, China, France, Russia and the United States — the permanent members of the U.N. Security Council. All had detonated a nuclear weapon by 1967, the cutoff date in the treaty to qualify for the designation.

How long has Israel had nuclear weapons?

Israeli leaders were intent on building a nuclear arsenal to safeguard the country’s survival soon after it was founded in 1948 in the wake of the Holocaust, historical records indicate.

The Israel Atomic Energy Commission was established in 1952, and its first chairman, Ernst David Bergmann, said that a nuclear bomb would ensure “that we shall never again be led as lambs to the slaughter,” according to the Jewish Virtual Library.

Israel began building a nuclear weapons development site in 1958, near the southern Israeli town of Dimona, researchers believe. A recently declassified U.S. intelligence report from December 1960, by the Joint Atomic Energy Intelligence Committee, stated that the Dimona project included a reprocessing plant for plutonium production. The report concluded that the project was related to nuclear weapons.

Around 1967, Israel secretly developed the ability to build nuclear explosives, according to the Arms Control Association. By 1973, the United States “was convinced Israel had nuclear weapons,” the Federation of American Scientists later wrote.

Israel is not among the three dozen countries — all in Europe or Asia — considered to be protected by the United States’ so-called nuclear umbrella. That protection not only serves as an American deterrent against adversaries but also aims to encourage the countries not to develop their own nuclear weapons.

Experts said that the fact that Israel was not part of the American nuclear umbrella was another unspoken acknowledgment that Israel had its own atomic weapons and did not need protection or deterrence.

“Ultimately, there is a sense of responsibility that Israel’s security rests with Israel, and they will do what is necessary to provide for that,” Mr. Bollfrass said.

Has Israel used its nuclear weapons in war?

No.

The Jewish Virtual Library, which is considered among the world’s most comprehensive Jewish encyclopedias, has cited reports that Israel prepared its nuclear bombs during the Arab-Israeli wars of 1967 and 1973, but the weapons were not used.

There have been a few reports over the past 50 years that Israel has tested its nuclear weapons at underground sites, including in the Negev desert in southern Israel.

The most prominent episode — and one that remains under debate — was in September 1979, when an American satellite designed to detect nuclear explosions reported a double flash near where the South Atlantic and Indian oceans meet. Some scientists believed that the double flash was likely to have been the result of a nuclear test, by Israel or South Africa, or possibly by both.

Israel denied involvement in what is known as the Vela incident, for the satellite’s name. Former President Jimmy Carter’s White House diaries, published in 2010, cited “growing belief” at the time that Israel had tested a nuclear explosion near the southern tip of South Africa. But that was never proven, and “relevant documents for the Vela incident are still classified,” the scientists Avner Cohen and William Burr wrote in 2020, citing the diaries.

Where does Israel build its nuclear weapons?

It’s widely believed that Israel’s nuclear weapons program is housed in Dimona.

Experts said it appeared that inspectors from the International Atomic Energy Agency had never been to the site, and that there was no agreement with Israel that would allow the U.N. watchdog agency to monitor it. American scientists visited Dimona in the 1960s and concluded that the nuclear program there was peaceful, based on increasingly limited inspections, historical records show. But there is no public evidence that American inspectors have been back since.

Satellite photos show new construction at Dimona over the past five years. At a minimum, experts said, the facility is undergoing repairs and much-needed modernization.

There is also a growing belief among some experts that Israel is building a new reactor in Dimona to increase its nuclear capability. A report released this week by the Stockholm International Peace Research Institute said Israel appeared to be upgrading a reactor site there to produce plutonium, which can be used both for nuclear weapons and some peaceful purposes, like in space.

Because of its secrecy, Dimona has long been a symbol of fascination and, to some, anger over Israel’s nuclear weapons program.

In a rare public event at the site in 2018, Prime Minister Benjamin Netanyahu of Israel used it as a backdrop to warn enemies that “those who threaten to wipe us out put themselves in a similar danger — and in any event will not achieve their goal.”

Although analysts said the group remained a threat, it was unclear how much firepower Hezbollah could bring to bear after losing much of its arsenal and many of its senior commanders during its 14-month war with Israel.

Once a formidable militia, Hezbollah was left battered by the conflict and has struggled to recover under a fragile cease-fire signed in November. As a result, the group has little incentive to risk provoking a new Israeli offensive, according to analysts.

Hezbollah's absence from the fighting in recent days underscored the new reality for a group long positioned by Tehran as its first line of defense against Israel and reflected the broader weakening of Iran’s network of regional allies and proxies.

After Israel began airstrikes inside Iran on Friday, Lebanon’s government relayed messages to Hezbollah via the Lebanese military, urging the group not to intervene, according to one of the Lebanese officials. Lebanon’s new government has pledged to disarm all armed groups inside the country, including Hezbollah, but has yet to set a timeline on the process.

Those messages were echoed on Monday by Lebanon’s president and prime minister who stressed — without naming Hezbollah directly — that the country must stay out of the conflict. The crisis-hit nation is still reeling from Lebanon’s deadliest war in decades, with swaths of the country in ruins and no indication who will foot the multibillion-dollar reconstruction bill.

During a cabinet session on Monday, President Joseph Aoun insisted on “making every possible effort to keep Lebanon away from conflicts that do not concern it,” according to a statement from his office.

Western officials have similarly cautioned Hezbollah in recent days to stay out of the fighting, according to a senior Western diplomat who communicates with the militant group. Hezbollah so far appears to be wary of making a misstep and understands that any attack against Israel from Lebanon would not serve its interests, said the official, who requested anonymity to discuss the sensitive issue.

Hezbollah’s media office did not immediately respond to a request for comment. The group said in a statement on Friday that Israel’s attack on Iran was a dangerous escalation that threatened to “ignite the entire region,” but it notably stopped short of any pledge to respond militarily.

However, Lebanon is also home to an array of other armed groups, among them Palestinian factions including Hamas, whose primary power base is the Gaza Strip, where Israel is in the midst of another war.

Hamas was accused in March of firing rockets into Israel from Lebanon, one of many actions on both sides of the conflict in defiance of the cease-fire. Hours later, the Israeli military carried out airstrikes in Beirut’s southern suburbs for the first time in months, leading the Lebanese government to issue stern warnings to Hamas and arrest several Palestinian operatives.

Fearing a repeat of such rocket fire, the Lebanese military has moved to bolster its presence and enforce security measures in southern Lebanon in recent days, according to two senior Lebanese security officials who requested anonymity to discuss sensitive military matters.

The reinforced measures include increased army patrols and more vehicle searches at checkpoints, which are intended to prevent militants from firing into Israel from Lebanon and triggering an escalation, one official said.

Lebanon’s prime minister, Nawaf Salam, said on Monday that Lebanon must be spared “any involvement, in any form, in the ongoing conflict,” according to a government statement.

Hwaida Saad contributed reporting.

The aircraft would also be capable of refueling B-2 bombers flown out of the United States on their way to targets in Iran, presumably starting with Fordo, the under-the-mountain nuclear enrichment center that Iran built around 15 years ago to withstand the heaviest strikes.

Mr. Trump’s increasingly martial tone — a sharp reversal from his announced confidence two weeks ago that a nuclear deal with Iran was easily within reach — came only hours after he cut short his attendance at the Group of 7 summit in Alberta, Canada, saying he needed to return to Washington to deal with the situation in the Middle East.

His immediate decision is whether to deploy America’s largest conventional weapon — the 30,000-pound Massive Ordnance Penetrator — to attack Fordo, Iran’s deepest nuclear enrichment site.

While Mr. Trump suggested that the United States had control of Iran’s skies, the only visible combatant has been Israel, which has been using American-made fighter jets. Israeli officials have said that they have been able to destroy much of Iran’s air defenses.

In one of his messages Tuesday, Mr. Trump threatened Iran’s supreme leader, Ayatollah Ali Khamenei, saying “we know exactly where” he is. But he added that “we are not going to take him out (kill!), at least for now.”

He added, “Our patience is growing thin.”

Killing foreign leaders violates executive orders signed by a series of presidents dating to Gerald Ford. The operative one states: “No person employed by or acting on behalf of the United States government shall engage in, or conspire to engage in, assassination.”

In his own social media post, Vice President JD Vance also hinted that the United States could step up its engagement. Mr. Vance said that Iran has no need for nuclear fuel enriched above the level needed for commercial power. Mr. Trump, he wrote, “has shown remarkable restraint,” but “may decide he needs to take further action to end Iranian enrichment.”

“That decision ultimately belongs to to the president,” Mr. Vance wrote.

The vice president acknowledged the sentiments of some in the Republican Party who have called for staying out of conflicts in the Middle East, writing “of course, people are right to be worried about foreign entanglement after the last 25 years of idiotic foreign policy,” a period of time that encompasses Mr. Trump’s first term and the Bush, Obama and Biden administrations. But, he added, “I believe the president has earned some trust on this issue.”

It remains to be seen whether Mr. Trump will decide that the United States should join Israel’s efforts, with American offensive capability. But the decision to launch a full-on attack on Iran’s facilities would easily be in the gray area between the president’s powers as commander in chief and the Constitution’s mandate that only Congress can declare war.

Officially, the United States has said nothing about joining offensive operations with Israel. Defense Secretary Pete Hegseth said only that American forces were maintaining a “defensive posture.”

It was also unclear whether Mr. Trump, who has talked repeatedly about seeking a diplomatic solution, now believes the time for negotiation is over. One senior official indicated on Tuesday that there may be a short round of “coercive diplomacy,” in which Iran is given a brief period of time to agree to the terms that Mr. Trump’s special envoy, Steve Witkoff, presented two weeks ago. That called for a gradual end to all enrichment on Iranian soil, a condition the Iranians said publicly they would reject.

But on his flight back to Washington from Canada early Tuesday morning, Mr. Trump told reporters on Air Force One that he was not in the mood to continue talks with Iran, which were scheduled for last Sunday before Israel began mounting its attacks.

Mr. Trump said that he was seeking a result that was “better than a cease-fire” between Israel and Iran. Asked what would qualify, he said “an end, a real end, not a cease-fire, a real end.”

It was also unclear what Mr. Trump meant when he demanded Iran’s “unconditional surrender.” The United States has not declared war on Iran, and it has said it is not pursuing regime change there, though in Mr. Trump’s first term many of his aides talked openly of trying to speed the collapse of its government.

Iran has sent indications it is still willing to negotiate, but only if Israel’s attacks on Tehran and nuclear and missile sites cease.

The Israelis have shown no interest in letting up. And many Iran analysts believe the Iranian leadership, shocked by the killing of many top military leaders and scientists, would likely not reverse its insistence on retaining enrichment capability, even if the alternative is continued assaults on its spread-out nuclear facilities.

Their time may be running out. By deploying the refueling KC-135 and KC-46 aircraft to air bases in Italy, Spain, Germany and Greece, U.S. officials said that the Air Force was building an “air bridge” in Europe should installations in the Middle East come under Iranian attack.

Deploying the aircraft closer to the Middle East also provides the Pentagon more options if it needs to defend bases in the region, officials said.

“Protecting U.S. forces is our top priority and these deployments are intended to enhance our defensive positions in the region,” Mr. Hegseth said on X on Monday.

But the moves also put in place an elaborate refueling network for B-2 bombers, should Mr. Trump order them to fly the nearly 7,000 miles from Whiteman Air Force Base in Missouri to attack the Fordo site.

Fordo is Iran’s most heavily fortified enrichment center, built deep inside a mountain to protect it from an attack. Only the U.S. military has the 30,000-pound bomb capable of even reaching it.

Its size — 20 feet long and 30,000 pounds — means that only the American B-2 stealth bomber can carry it.

On Capitol Hill, the president’s public flirtation with joining Israel’s bombing campaign has reawakened a long-dormant debate about clawing back congressional power to declare war.

In the House, a Democrat and a Republican teamed up on Tuesday to introduce a resolution that would require congressional approval before U.S. troops could engage in offensive attacks against Iran.

The measure by Representatives Ro Khanna, Democrat of California, and Thomas Massie, Republican of Kentucky, underscored a view held by many in Congress that Mr. Trump should not be able to decide on his own whether the United States wades deeper into the conflict.

Thirteen additional Democrats signed on to the resolution, but no Republicans were so far supporting the effort.

Senator Tim Kaine, Democrat of Virginia, on Monday introduced a similar resolution.

Both efforts face long odds, given Republican reluctance to challenge Mr. Trump’s power. But with some lawmakers in both parties openly resisting further U.S. involvement, they are likely to prompt a vibrant debate. The measures enjoy a special status that will compel Congress to vote on them one way or the other in the coming days.

Still, Speaker Mike Johnson has, so far, been successful in deflecting efforts to force Republican members to take any vote that would require them to challenge Mr. Trump’s authority, and he could seek a procedural solution that would allow him to circumvent a vote on a war declaration.

In the Senate, defense hawks cheered Mr. Trump’s bellicose posture.

Senator Lindsey Graham, Republican of South Carolina, reiterated his stance that he supported U.S. involvement in the conflict against Iran.

“I want us to go all in to help Israel destroy their nuclear programs,” he said on Tuesday, adding that he had spoken to Mr. Trump Monday evening about his views.

When asked what role Congress should have in authorizing offensive strikes in Iran, Senator Bernie Moreno, Republican of Ohio, deferred to Mr. Trump.

“I have total faith and confidence in the president of the United States,” he said in an interview on Tuesday.

Robert Jimison and Eric Schmitt contributed reporting.

But as Israel pounds Iran with airstrikes that it says are aimed at the country’s nuclear and missile programs, analysts say the assault increasingly threatens the survival of Iran’s government and may in effect be turning into a regime change operation.

That could leave Mr. Trump trying to avoid entanglement in the sort of conflict he has spent years portraying as the definition of insanity.

Israeli officials say their attacks are an urgent response to Iran’s advances in its nuclear program. But there are growing signs that their aims are expanding.

During an interview on Fox News on Monday, Prime Minister Benjamin Netanyahu of Israel was asked whether regime change was an explicit goal.

“It could certainly be the result, because Iran is very weak,” he said. He added that “the decision to act, to rise up, at this time, is the decision of the Iranian people.”

But Mr. Netanyahu has also appealed to Iran’s population — which has risen in protest many times in recent years, only to be brutally repressed — to do just that. “The time has come for you to unite around your flag and your historic legacy by standing up for your freedom from an evil and oppressive regime,” he said last week.

In a Monday interview with ABC News, Mr. Netanyahu also said that Israel might choose to “end the conflict” by killing Iran’s supreme leader, Ayatollah Ali Khamenei.

“This is the name of the game,” said Vali Nasr, a professor at the Johns Hopkins School of Advanced International Studies.

“It’s not how successful Israel is in taking out Fordo,” the Iranian nuclear facility buried deep in a mountain. “It is now measured by how successful they can be in taking out the Iranian state.”

Mr. Nasr noted that Israel has been striking targets with no direct connection to Iran’s nuclear program, including a Monday attack on the headquarters of Iran’s state broadcasting network. “They are trying to take away the coherence of the state — not only to conduct the war, but to function,” he said.

Mr. Trump has so far limited America’s known role to the defense of Israel. But in a post on Truth Social on Tuesday, he suggested a willingness to eliminate Mr. Khamenei, saying “we know exactly where” he is hiding. “We are not going to take him out,” he wrote, adding: “At least not for now.”

And the president associated himself with Israel’s war effort, writing in a separate post: “We now have complete and total control of the skies over Iran,” with the support of American military hardware. (Despite Mr. Trump’s use of “we,” the United States is not flying missions over Iran, U.S. officials say.)

A full collapse of the Iranian state, meanwhile, would create new risks — including the need to secure Iran’s nuclear material — that would greatly increase the prospects of American involvement in the conflict.

Israel’s primary goal may be the destruction of Iran’s nuclear program, said Michael Makovsky, president and chief executive of the Jewish Institute for National Security of America, which has backed military action against Iran.

Mr. Makovsky added, however, based on his conversations with senior political and military officials there, that Israel has always known that such a campaign could also have broader political consequences.

“They’ve hoped that, because the regime was so weak, military action could lead to the people bringing down the regime,” he said.

Iran’s leadership may share that assessment. In April, The New York Times reported that Mr. Khamenei agreed to nuclear talks with President Trump earlier this year only after top Iranian officials warned him that failure to negotiate could lead to attacks by Israel or the United States. That, they said, could threaten the survival of their government.

Even some supporters of using force to seek a change in Iran’s government are careful to avoid the catchphrase that was used often during the Iraq War and subsequent Western interventions in the Middle East. They include the 2011 NATO air campaign in Libya that overthrew the dictator Muammar Gaddafi but triggered years of chaos and civil war.

Mr. Trump himself has tried to engineer the fall of at least one foreign government, the leftist dictatorship of Venezuela’s Nicolas Maduro, which he choked with economic sanctions in his first term. But he never described his policy as regime change.

“I use the term ‘regime collapse,’ versus ‘change,’” Mr. Makovsky said, “because the term ‘regime change’ is toxic in Washington. Everyone thinks about 2003.”

In March of that year, President George W. Bush invaded Iraq and deposed its strongman, Saddam Hussein. The ensuing effort to install a friendly democratic government in Baghdad cost thousands of American lives and hundreds of billions of dollars, and to many, discredited U.S. interventionism.

The key distinction, Mr. Makovsky said, is that a regime collapse strategy does not presume to remake Iran’s government. “My view is that we shouldn’t do that. But our objective should be to pressure the regime every way possible so that the Iranian people bring it down.”

For now, Mr. Trump has kept some distance from Israel’s war. But his supporters are divided on his approach, with some accusing Mr. Trump of betraying his principles.

On Monday, two of Mr. Trump’s most prominent supporters, the former Fox News host Tucker Carlson and the former Trump White House aide Steve Bannon vented their frustration on a radio show hosted by Mr. Bannon.

“The point of this is regime change,” Mr. Carlson insisted, arguing that Mr. Trump was being led by Israel into what could become a “world war.” “I don’t want the United States involved in another Middle East war,” he added.

Mr. Bannon agreed, citing Mr. Netanyahu’s comments on Fox and saying, “This is a total regime change.”

“This thing has not been thought through,” he added. “It does not have the support of the American people.”

Analysts said it would be especially difficult for Mr. Trump to avoid being drawn into the aftermath of a government collapse. “The U.S. just can’t not be involved,” said Mr. Nasr, noting that, among other things, it would be essential to secure Iran’s stockpile of uranium amid any political chaos.

Some analysts fear that Iran could descend into chaos and even civil war, radiating instability throughout the Middle East. Although one U.S. official said that Mr. Khamenei had put in place a succession plan, and that in the event of his killing or overthrow Iran’s religious-military establishment would be likely to retain control — possibly with an even more extreme figure.

Even so, few in Washington would mourn the fall of a theocracy that sponsors terrorism and has for decades called for the destruction of America and Israel. And some prominent Republicans are calling for that outcome.

“I think it is very much in the interest of America to see regime change,” Senator Ted Cruz of Texas said on Fox News on Sunday. “I don’t think there’s any redeeming the ayatollah.”

Another Republican senator, Lindsey Graham of South Carolina, told CBS News on Sunday he would “love for the regime to fall,” but added that “is not the purpose of this attack — yet.”

Ben Rhodes, a former deputy national security adviser under President Obama who was deeply involved in Iran policy, said that even some Democrats are wondering whether to root for Iran’s government to collapse.

Mr. Rhodes fears that initial success of Israel’s military campaign has created the illusion of a simple solution, something that reminds him of the early stages of another Middle East conflict more than 20 years ago.

“It looked great when the statue of Saddam Hussein fell” in the spring of 2003, Mr. Rhodes said.