The order was given just before 7pm in Washington to drop the heaviest conventional bombs ever used in combat.

A fleet of B-2 bombers had been airborne for nearly 37 hours, having taken off from the Whiteman Air Force Base in Missouri on Friday and refuelled several times mid-air.

As the bombers – their advanced stealth capacity making them virtually invisible to Iranian radar – closed in on their targets, guided-missile submarines from the US Navy also moved into position. Somewhere in the Arabian Sea, a fleet of converted Ohio-class vessels, each capable of carrying up to 154 warheads, stood ready.

Everything now awaited the final order from the commander-in-chief.

Donald Trump had been here before. In 2019, the US military was “cocked and loaded” to strike Iran. Bombers were in the air, missiles on US warships locked onto their targets.

Then, with 10 minutes to spare, the president called it off – an unprecedented, very public reversal of a major military operation.

This time, there was no such hesitation, at least visible to the public. The dial of history turned.