The military background to what took place during these War Cabinet meetings is important. When discussions began on 26 May, Operation DYNAMO had only just been put into effect. About 25,000 British troops were extracted from the harbour and beaches of Dunkirk over the next forty-eight hours. Whether the Royal Navy could rescue many more soldiers than this was still not clear. If Dunkirk fell to the Germans quickly, as it seemed it might, only a small fraction of the total British force trapped in the Flanders pocket would get away. ‘Of course, whatever happens at Dunkirk, we shall fight on,’ Churchill said ‘quite casually’ at his meeting with the outer Cabinet on 28 May. 14 At the time, though, he had no way of knowing whether that was a pledge he could hold to. His statement to the Commons that evening was terse and gloomy. The House, he warned, ‘should prepare itself for hard and heavy tidings’.15 As Mason-MacFarlane’s apocalyptic briefing in the Berkeley Hotel illustrates, the Army itself had no confidence in success. What would have happened if DYNAMO had failed and most of the British troops in France and Flanders had been forced to surrender? Presumably, Churchill would have wanted to fight on regardless. There would have been voices in the Cabinet and the service ministries demanding the same. The RAF and RN might have insisted that the homeland was still safe from invasion by air and sea, for the time being anyway. But consider the context. The Germans would have just captured almost all the British Army. Hitler would be holding several hundred thousand soldiers, most of the country’s trained military personnel, as hostages. If, on 4 June 1940, Churchill had had to return to the House of Commons to announce not ‘a miracle of deliverance’ at Dunkirk but a dreadful mass capitulation, lacking any redeeming counter-narrative to soften the blow of defeat, it’s hard to imagine him being able then to go on to summon up much enthusiasm to fight on Britain’s beaches. At the very least, Halifax would surely have seized the opportunity to reopen the discussion of peace talks that he had been forced to abandon on 28 May. Churchillian hagiography today would have it that it was the prime minister’s iron will alone which kept Britain in the war in 1940. ‘Take away Churchill,’ according to Charles Krauthammer, ‘and Britain would have settled with Hitler – or worse. Nazism would have prevailed.’16 Boris Johnson echoed the same view in 2014, when he wrote: ‘without Churchill, Hitler would almost certainly have won […] only he could have done it.’17 But it was the success of DYNAMO, not Churchill imposing his resolve, however formidable, on his foreign secretary, that clinched the matter of whether Britain fought on in May 1940. Prime ministerial will was important, to be sure. But it was never enough by itself.