Crucially, this is not Syria, where US intelligence has repeatedly confirmed that Bashar al-Assad gassed his own people. On Syria, the US assessed; the US acted. The US’s Syria analysis may actually be unraveling at present in the media, but questioning that intelligence remains, for the US establishment at least, the ‘realm of conspiracy theory’ as New Yorker writer Dexter Filkins aptly put it.

Though Syria may be a proxy fight in the Iran standoff, Iran itself is different. In 2018, Trump nullified a popular deal inked by a popular president. He may have been right to do so, but his action cast further doubt on an administration already ruinously distrusted by elites. This is not 2003, when George Bush led America into Iraq. Nor is it 1998, when Bush’s predecessor Bill Clinton marshaled a bipartisan spirit for airstrikes on Saddam. Further, Trump’s own attacks on US intelligence agencies and a government ‘deep state’ undermine public faith in the government’s trustworthiness.

Military retaliation would be a heavy lift. If Trump raises the tempo of the war drums on Iran, he’ll be going it alone. The president who won the White House by eviscerating US errors in Iraq should reject a distressingly similar conflict with Iran.