Later, as rioters roam inside the building, smoking joints under the rotunda and sprawling across the Speaker’s podium (“I just wanna let you guys know this is, like, the most sacredest place,” says a harried officer), police hold back some 7,000 or 8,000 more at the West Terrace tunnel.

America teetered on the brink of martial law, Reed says. When an officer is dragged into the mob, “you can see that there are different impulses within the crowd: one is to smash his face in and kill him – and the other is to save him.”

Had the House of Commons been in comparable jeopardy, he says, “ there would have been massive bloodshed – with that level of threat, I think police would have definitely opened fire. It’s just astonishing that the Capitol police didn’t.”

Instead, as an officer says in the film– and as the footage shows to be miraculous – huge loss of life was averted on both sides. The squall passes when, after four hours, Trump finally tells his adoring, warring supporters to go home.