At the same meeting, Air Chief Marshal Sir Trafford Leigh-Mallory, the air commander-in-chief, outlined the plan ‘to establish a belt of bombed routes through towns and villages thereby preventing or impeding the movement of enemy formations’. He asked whether he was free to proceed ‘in view of the civilian casualties which would result’. Eisenhower announced his approval ‘as an operational necessity’. It was decided to drop leaflets to the French to warn them.

The fate of French civilians was just one of many worries. As supreme commander, Eisenhower had to balance political and personal rivalries, while maintaining his authority within the alliance. He was well liked by Field Marshal Sir Alan Brooke, the Chief of the Imperial General Staff, and by General Sir Bernard Montgomery, the commander-in-chief of 21st Army Group, but neither rated him highly as a soldier. ‘There is no doubt that Ike is out to do all he can to maintain the best of relations between British and Americans,’ Brooke wrote in his diary, ‘but it is equally clear that he knows nothing about strategy and is quite unsuited to the post of Supreme Commander as far as running the war is concerned.’ Monty’s characteristically terse judgement on Eisenhower after the war was: ‘Nice chap, no soldier’.

These opinions were certainly unfair. Eisenhower demonstrated good judgement on all the key decisions over the Normandy invasion and his diplomatic skills held a fractious coalition together. That alone represented a considerable feat.