PERHAPS HE CAME to believe his own myth, the aura of invincibility he worked so hard to cultivate. Early on January 3rd General Qassem Suleimani, Iran’s most storied and feared commander, stepped off a plane from Syria or Lebanon at Baghdad’s international airport. He climbed into a waiting convoy alongside the leader of an allied militia—a seeming lapse in security, the two men travelling together, that suggests the general felt safe in Iraq. Minutes later he was dead, his vehicle blasted into scrap by an American drone flying overhead.

Few believed the news as it trickled out on social media and satellite television. Within hours, though, both sides had confirmed the rumours. The supreme leader of Iran, Ayatollah Ali Khamenei, praised General Suleimani as a martyr and vowed “severe revenge”. President Donald Trump was uncharacteristically restrained: he simply tweeted an image of an American flag. He left the formal announcement to the Pentagon, which called this a “defensive action”.

It was a dizzying escalation to cap off a dizzying week. On December 27th dozens of rockets hit an Iraqi military base near Kirkuk, killing an American contractor. America responded by bombing five bases used by Kataib Hizbullah, an Iranian-backed Shia paramilitary group. At least 25 of its men were killed. The group soon tried to storm the American embassy in Baghdad, besieging it for almost a full day.

Then came the strike that killed General Suleimani and seven others, including Abu Mahdi al-Muhandis, the founder of Kataib Hizbullah and the head of an umbrella group of pro-Iranian militias. The long conflict between America and Iran has mostly been fought through proxies, spies and sanctions. This was tantamount to an act of war—a rare overt strike with profound consequences for the region.

General Suleimani led the Quds Force, a branch of the Islamic Revolutionary Guard Corps (IRGC) that operates outside Iran. He was Iran’s main interlocutor with Hizbullah, the Lebanese Shia militia and political party. In 2006, when it fought a month-long war against Israel, General Suleimani was in Lebanon to help oversee the campaign. He later lent his support to Bashar al-Assad, the embattled Syrian dictator, and to the Houthis, a Yemeni militia fighting a brutal war against a Saudi-led coalition. Supporters saw him as the face of the so-called “resistance” against America and Israel. To his detractors he was more akin to a viceroy, an emblem of Iran’s deep and destructive influence across the region. In Baghdad’s Tahrir Square, where Iraqis have spent months protesting against Iran’s meddling in their country (among other things), news of General Suleimani’s death was met with cheers.

Americans knew him as the man who tormented their troops during the occupation of Iraq. General Suleimani trained Shia militias and supplied them with “explosively formed penetrators”, roadside bombs capable of punching through the armour on American vehicles. They killed hundreds of soldiers (one in every six American combat fatalities in Iraq were attributable to Iran, says the Pentagon). Yet George W. Bush would not allow cross-border raids to strike at the IRGC, and officers detained in Iraq were released. Israel had opportunities to kill the general but passed them up because of American pressure. Mr Trump, as is his wont, broke with this long precedent.

The question now is how General Suleimani’s successors will respond. Many American analysts fret that Mr Trump is blundering into a war. But Iran will not seek an open confrontation it would surely lose: its antiquated military is no match for America’s. Instead it will rely on the asymmetric tactics that General Suleimani perfected. It could hit vulnerable infrastructure in Gulf states, or fire rockets at Israel. It could strike at American diplomats and military personnel in Iraq and elsewhere. (The State Department has urged Americans to leave Iraq.)

Indeed, Iran and its proxies have done all those things over the past year. Until now Mr Trump has been hesitant to respond (while often offering to meet with Iran’s leaders). He ordered air strikes after Iran shot down an American drone in June, but recalled the planes when he decided the response was disproportionate. A September missile attack on two oil fields in Saudi Arabia, which America blamed on Iran, went unanswered. In typically chaotic fashion, he has now zagged from inaction to major escalation.

That raises the risks of an uncontrolled cycle of tit-for-tat retaliation. The regime in Tehran cares about self-preservation. But of late it has also seemed confident, even cocky. The attack on Saudi Aramco, itself an unprecedented strike on world oil supplies, followed months of Iran harassing tankers and warships in the Persian Gulf. If the IRGC hits back hard, it is impossible to predict what Mr Trump might do.

In the short term the Iranian regime may bide its time and use the killing to whip up nationalist fervour at home. General Suleimani was a popular figure in an otherwise unloved regime. Only Mr Khamenei appeared on more of Tehran’s billboards. The feeling of admiration was not universal: General Suleimani was part of a security apparatus that ruthlessly crushes dissent. “It’s good to see there really are some checks and balances,” says an academic in Tehran. Still, a state funeral, and the mourning that follows, offers a distraction from the crumbling economy that prompted a week of nationwide protests in November.

America will have to rethink its own regional position. It may be impossible to keep American troops in Iraq, where they train the Iraqi army and keep tabs on the jihadists of Islamic State (IS). The Iraqi government might order the Americans out, long a goal of pro-Iranian lawmakers. Even if it does not, the Pentagon may decide it is too hard to protect American troops in a hostile land. Withdrawing from Iraq may also end America’s rump deployment in Syria, which relies on Iraq for logistics. With American troops gone IS would find more space to regroup. American diplomats and spies face the threat of kidnapping or assassination, both of which the IRGC has done in the past. Corporations may have similar concerns about staff working on Iraqi oil fields and elsewhere.

General Suleimani was a singular commander, in both his skill and his standing. He seemed to be everywhere, popping up on battlefields all across the Middle East. Some saw him as a future leader of Iran—the real power behind the clerics. His death is a blow to the ambitious regional policy he oversaw, far more significant than the raids that killed Osama bin Laden or Abu Bakr al-Baghdadi, the leaders of al-Qaeda and IS. By the time of their deaths, those men were mere figureheads at the helm of diminished organisations. General Suleimani was cut down in his prime, at a time when Iran still wields great power across the region.

Less clear is whether the strike will advance America’s stated goal of creating a less belligerent, more restrained Iran. Though it now seems a distant memory, the current tensions began with Mr Trump’s decision in 2018 to withdraw from an agreement that lifted some sanctions on Iran in exchange for curbs on its nuclear programme. Any hope of renegotiating that deal—of finding a diplomatic solution to a steadily worsening conflict—probably died with General Suleimani.