Iran’s escalation left the Trump administration in a quandary. The president likes grand diplomatic gestures. But his administration’s withdrawal from the Iran deal—combined with its absurdly maximalist demand that, as a condition for any future nuclear agreement, Iran entirely capitulate to Saudi Arabia in the two countries’ contest for regional influence—has made a diplomatic solution to the crisis virtually impossible. In June, Trump’s then-national security adviser, John Bolton, argued for meeting Iran’s provocations with force. But Trump, convinced that his supporters want no more Middle Eastern wars, called off an attack aimed at punishing Iran for the drone strike. The attack on the drone didn’t kill any Americans, Trump explained. If it had, that would have made “a big, big difference.”

In backing down, he thus established a red line. And last week, Iran’s proxies crossed it. An Iranian-backed Iraqi militia, Kataib Hezbollah, fired on an Iraqi military base, wounding four American servicemen and killing an American contractor. This time, the Trump administration did respond with force: On Sunday, it launched airstrikes against the militia’s forces in Iraq and Syria, killing 24 people and wounding 50.

But if Trump’s non-response made America look weak in June, his military response on Sunday set off a chain of events that has made America look even weaker. On Tuesday, following funeral services for the dead militiamen, thousands of supporters of Kataib Hezbollah and other pro-Iranian militias stormed the U.S. embassy in Baghdad, shouting “death to America.” Outraged by the U.S. attacks, many of Iraq’s top clerics and politicians are now demanding the withdrawal of all American troops. On Tuesday, Abbas Kadhim, director of the Iraq initiative at the Atlantic Council tweeted that, “I expect the days of the large American diplomatic & business presence in Iraq to be numbered.” Liz Sly, The Washington Post’s bureau chief in Beirut, predicted an endgame reminiscent of Saigon in 1975. “After today,” she tweeted, “how do the Americans trapped inside the embassy leave except by helicopter?”