War by miscalculation can hardly be ruled out, but for the moment, both the Trump administration and Iran seemed to have decided to lower the temperature of the crisis. Neither side wants war. Foreign minister Javad Zarif’s tweet about Iran’s retaliation for Soleimani’s killing was notably measured: “Iran took and concluded proportionate measures in self-defense under Article 51 of the UN Charter targeting base from which cowardly armed attack against our citizens & senior officials were launched. We do not seek escalation or war, but will defend ourselves against any aggression.”And the fact that no Americans were killed gave President Trump a useful off-ramp for avoiding escalation.

The two countries now seem likely to return to the cycle of conflict that has dominated their relations since the Iranian revolution. The trauma of Americans being held hostage has paralysed US policy for forty years, save only for President Obama’s brief opening through the nuclear agreement, one quickly quashed by the Trump administration.

For those decades, American hostility has been the best thing going for the Iranian regime, just as it was for Fidel Castro in Cuba. Independent Iranians, including this piece’s co-author, judge that but for Washington’s encouragement of Iraq to attack Iran in 1980, the revolution might not have survived.

As Shakespeare counselled in Henry IV, “make it your policy to focus the distracted minds of the people on foreign wars.” This time around, the assassination of Qassem Soleimani came just after one of the most serious internal protests Iran had seen. It is hard to judge how dangerous the protests were for the regime, but what is easy to judge is that nothing would be more effective at muting internal dissent than a demonstration of the US threat, and killing Soleimani provided just that.

The immediate wild card is the shooting-down of the Ukrainian airliner by Iranian forces, apparently by accident. That has sparked new protests, but understanding Iranian public sentiment is as complex as the politics of the region. The numbers in the street this week have been very small by comparison to the turn-out for Soleimani’s funeral (though it should be noted that many of those marching for Soleimani were honouring a war hero, not necessarily the regime he served).

And the episode could only serve as a reminder of America’s shooting down of an Iranian airliner in 1988, killing 290 people. In his tweet, Zarif blamed the Ukrainian Air catastrophe on American “adventurism,” presumably a suggestion that absent Soleimani’s killing, Iranian forces wouldn’t have been on hair-trigger alert. Finally, Trump’s tweet in Farsi may enjoy a moment of popularity, but it certainly does not help protestors who want to be seen as independent and genuine rather than stooges of the US.

Before the downing of the Ukrainian airliner, the Iranian regime seemed the clear winner in the crisis: internal opposition was quieted; the United States had been widely condemned as aggressor, and the Iraqi parliament had voted to expel Americans. Iran, on the defensive, seems to have thought that it could use the crisis to drive America from Iraq, and perhaps the region more generally. In that it may yet succeed.

Parsing Trump’s motivations is a fool’s errand, but the immediate driver seems to have been pure pique at watching Iranians encourage Iraqis to riot at the US embassy in Baghdad. Beyond pique, the killing reflected Trump’s playbook: act tough and the other side will yield. That may work in the wilderness of New York real estate, but it surely hasn’t worked for Trump in US foreign policy. Indeed, killing Soleimani could only give advantage to Iran’s hard-liners.

More than a week into the crisis, no US strategy is yet visible. Improvising, perhaps Washington can turn Soleimani’s assassination into face-saving negotiations with Iran. But there seems little appetite to move in that direction. And as Lyndon Johnson said, famously, “while you’re saving your face, you’re losing your ass.”

A second wild card is the US election. Trump, facing impeachment, is bound to be desperate to show some foreign policy success. Killing Soleimani didn’t force Iran to the negotiating table. We can only hope that it doesn’t take a war to fulfil his presidential ambitions, for, in any event, he is taking a big gamble on global peace to secure his election victory.