Fears about Iran’s nuclear program among Western and Arab nations have grown in recent years because the Islamic Republic has enriched uranium far beyond the levels needed for civilian purposes such as fueling nuclear power plants. It’s processing uranium almost to the levels required to make a bomb, without giving a clear reason why.

The US strikes could lead to attacks on American assets in the Middle East. Iran’s Supreme Leader Ayatollah Ali Khamenei warned Washington of “irreparable damage” if it bombed his country.

The US will likely have to put its troops on high alert. It has around 50,000 service members in the region, the bulk being in Kuwait, Qatar, Bahrain, the United Arab Emirates, Iraq and Saudi Arabia.

In Yemen, the Houthis, a militant group backed by Iran, issued fresh threats against US commercial and naval ships. Until a ceasefire in early May, the Houthis were regularly firing drones and missiles at Western vessels and warships in the southern Red Sea.

Iran’s retaliation could come in the form of cyber attacks against American or Israeli interests.

It’s also possible that Tehran opts to leave the nuclear Non-Proliferation Treaty, according to Ali Vaez, the director of the International Crisis Group’s Iran Project and a long-time analyst of the country’s atomic program. The NPT is the bedrock arms-control agreement that compels signatories to accept inspections from the IAEA. If Iran left, the world would get even less information about what remains of its atomic sites.

“I hope that the Iranians are measured in their response but there will be a response,” said Barbara Slavin, a distinguished fellow at the Stimson Center. “This is an act of war by the United States against a foreign country which has not attacked us lately.”

The New York Times reported that six B-2 bombers dropped a dozen of the 30,000-pound (13,600-kilogram) bunker-buster bombs on Fordow. It said two other B-2s dropped the same weapons on Natanz, which also has underground uranium enrichment facilities, and fired cruise missiles at Natanz and Isfahan.

Israel was notified in advance of the strikes, according to a person familiar with the matter who asked not to be identified discussing private deliberations. Israeli Prime Minister Benjamin Netanyahu said the US and Israel had coordinated fully on the attacks.

The likelihood of an imminent strike seemed to have eased when Trump’s team said on Thursday he would make a decision within two weeks. On Friday, the foreign ministers of France, Germany and the UK met their Iranian counterpart, Araghchi, in Geneva to try to get Tehran to restart nuclear talks with the US.

Iran had been in negotiations with the US for about two months, but called them off after Israel started bombing its territory. The two had made some progress toward a deal that would curb Tehran’s atomic activities in return for sanctions relief, but stalled on enrichment. Iran insisted it must be allowed to continue that process, even if to the low level needed for civilian purposes. Trump and Israel said it shouldn’t be able to carry out any enrichment at all.

Energy Prices

The war between Israel and Iran has evoked fears of conflict with high civilian casualties and that spreads to other countries in the energy-rich region, disrupting flows of oil and liquefied natural gas. Those concerns among world powers and investors will probably increase in light of the American intervention.

The most immediate impact on the global economy could be through higher crude and LNG prices. About a fifth of the world’s daily oil supply goes through the Strait of Hormuz, which lies between Iran and its Gulf Arab neighbors such as Saudi Arabia. One option for Iran would be to hit or hassle crude and LNG tankers passing through the area.

Brent crude closed on Friday at just over $77 a barrel, up 11% since the conflict began. Another rise when global markets reopen on Monday morning will further complicate the task of major central banks as they seek to slow inflation.

For days, Trump had faced conflicting advice from his supporters, after he campaigned on promises to keep the US out of foreign wars, pointing to American involvement in Afghanistan and Iraq this century. MAGA allies, including longtime Trump supporter Steve Bannon, have warned against any US intervention, insisting this is Israel’s fight to finish.

Other Republicans urged Trump to join the fight against Iran, arguing that Tehran was more vulnerable following Israel’s attacks. They said it was an opportunity to deliver on the president’s pledge that Iran’s regime would never be allowed to have a nuclear weapon.

The White House suggested in recent days that any strike would be limited. The president briefed Senate Majority Leader John Thune and House Speaker Mike Johnson, according to people familiar with the matter.

“This is not the start of a forever war,” Senator Jim Risch, an Idaho Republican and chairman of the Senate Foreign Relations Committee, said on X. “There will not be American boots on the ground in Iran. This was a precise, limited strike, which was necessary and by all accounts was very successful.”

Israel said its attacks on Iran were aimed at setting back or destroying its nuclear program. Those have seriously damaged Iranian military sites and some atomic facilities. They also neutralized Iran’s air defenses, giving Israeli planes dominance over Iran’s airspace and making a US strike easier.

While Israel has not said it is aiming to topple Khamenei and the Islamic Republic, its officials have said they hope their attacks undermine the regime, which has been an adversary to the US and Israel for most of the period since the Iranian revolution in 1979. That event saw the fall of a Western-friendly monarchy and the birth of a theocratic government.

Israel needed the US’s help in attacking nuclear sites because it lacked the heavy bombs and B-2 stealth jets required to destroy facilities buried deep underground at Fordow and Natanz.

Natanz’s above-ground buildings were already heavily damaged by Israeli strikes, but not its enrichment rooms underground. Fordow was largely unscathed by Israel’s attacks, according to the IAEA.

Tehran has responded to Israeli bombing by firing waves of ballistic missiles and drones at the Jewish state every day. There was another salvo against Israel hours after the US attacks.

While around 24 people have been killed in Israel and hundreds injured, according to the government, Iran’s attacks have waned in recent days, suggesting its trying to preserve its weaponry.

Iran’s government says at least 200 people, mostly civilians, have been killed by Israel.

“Iran is going to be facing a real dilemma, because they’ve already been dramatically weakened,” said Dennis Ross, who served as former US President Bill Clinton’s Middle East envoy and is now a fellow at the Washington Institute for Near East Policy. “They will try to do something to show they didn’t just capitulate or submit, but they have their own interest in trying to limit this.”

Iran’s ability to react may be limited by its economic weakness, with inflation running at around 40%. It is also largely isolated internationally. While allies such as Russia and China condemned Israel’s strikes and warned against US intervention, they’ve offered little concrete support to Tehran.

“Tehran is now in its nightmare scenario,” said Ryan Bohl, said a senior Middle East and North Africa analyst at risk consultancy Rane Network. “To act or to not act are equally dangerous. To essentially surrender is to invite internal challenges; to fight back is to invite an open US air campaign that could aim to overthrow the Islamic Republic.”

—With assistance from Natalia Drozdiak, Eric Martin, Courtney McBride, Erik Wasson and Steven T. Dennis.

(Updates with more details throughout.)

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