Winston Churchill’s only serious rival for the post of prime minister and No. 10 Downing Street in that lovely spring of 1940 was Edward Wood, Lord Halifax. He was foreign secretary. Halifax could have succeeded Neville Chamberlain by raising his hand (he had only one). But he held back.

Officially, he based his decline of the top job by saying a peer could not effectively govern from the House of Lords. He succeeded in demonstrating his aristocratic disdain of vulgar grabbing for power. He chose to miss the hubbub that morning of destiny for Britain and all that Britain had meant. He went to his dentist.

Savvy insiders thought that Halifax—seeing a disaster looming across the English Channel—may well have expected Winston Churchill to fail, and fail spectacularly. Better to let Winston be unhorsed.

Then, the smart money could urge Halifax to seize the day and be vaulted into the prime ministership—by acclamation. It was not for nothing that Lord Halifax was called “the Holy Fox.”

Winston Churchill had been prime minister barely two weeks. His political situation was precarious. When Churchill had replaced Neville Chamberlain on May 10, the ruling Conservative Party’s heart was still with Chamberlain.

When the new prime minister entered the chamber of the House of Commons, with a broken Chamberlain trailing him, it was Chamberlain who got an appreciative ovation from the Conservative benches. Winston’s acclaim came from the benches of the minority Labour Party and the much-diminished Liberals. This was ominous.

On that same May 10, Hitler had taken his private train closer to the French border to superintend his blitzkrieg. His sleek black train glided silently over sealed steel rails. The train was named Amerika. As historian John Lukacs says, at the moment of Churchill’s ascent, this was not a coincidence but “a spiritual pun.”

Now, with the army retreating to the French coastal city, Churchill’s war cabinet met daily and sometimes several times a day. Halifax had two requests. He wanted to deal with the Italians to cobble together a peace, and he urged a national day of prayer to aid in the evacuation of the troops in Dunkirk.

Halifax would never call his motions “demands.” That would not have been lordly. He had only to press those two points. All members of the war cabinet knew what a twin refusal would mean. Halifax would resign—and that would paralyze Britain with another political crisis in London while beset by a military crisis in France.

It was during these ten days in May 1940 that the fate of Britain was being decided on the beaches at Dunkirk. Five hundred thousand soldiers of the British Expeditionary Forces (BEF), with their French and Canadian Allies, were surrounded.

The surging mechanized German Wehrmacht was supported by Hitler’s Luftwaffe. If the air and land assault wiped out the Allied forces hunkering down in the sands, an invasion of England loomed.

Churchill had fought and bested the Conservative Party appeasers to come to power at the advanced age of 65. Now, he had no alternative. He had to appease somebody. It could not be the Italians.

He knew that the dictator Benito Mussolini had been a negotiator at Munich. The bald Duce was instrumental in the betrayal of Czechoslovakia.

It was to this man that Halifax would appeal. Lord Halifax would entrust the future of the British Empire to Benito Mussolini, who had betrayed every promise, every agreement, every understanding the Men of Munich thought they’d achieved there. Noble Lord Halifax could be fairly compared with the Bourbons of France: they forget nothing; they learn nothing.

Still, since Churchill could not trust Mussolini with anything, he had to give way to Lord Halifax on something—his national day of prayer. If Churchill did not pray himself, or even believe in the power of prayer, he knew that Halifax did. And the king did. And so did millions of ordinary British men and women.

With bad grace, Winston said he would go to Westminster Abbey, but for only ten minutes. It was there, or perhaps on another of his rare appearances, a young vicar welcomed Churchill. “Prime Minister,” the eager cleric said to him, “I should like to tell my parishioners you are a pillar of the Church, Sir!”

Almost growling, Churchill managed not to wear his bowler hat and smoke his ever-present Havana cigar. “You may tell your parishioners that I am a buttress of the Church: I support it—but from outside!”

Churchill had hoped to draw off 50,000 troops from the beaches. If they managed to evacuate 100,000, Churchill thought they could be reorganized to make a desperate stand in defending the Home Island against the expected onslaught, possibly a German attack from the air.

The English Channel was becalmed. Unseasonably, those 21 miles were “as still as a mill pond.” As it continued, Operation Dynamo swelled the numbers of evacuees from Dunkirk. Royal Navy and Canadian warships were joined by ferry boats, fishing boats, sailboats—an unprecedented mosquito fleet. One of the boats was even skippered by Sir Arthur Rostron, the rescuer of the survivors of the Titanic.

Hitler had a spasm of doubt. He could hardly believe his luck. He fretted that his panzersmight outrun their fuel and equipment. And there is a good chance the porcine Hermann Göring whispered in his ear a warning: “If the Wehrmacht wins everything, they and not your loyal Nazi Luftwaffe will be strengthened. We can do this for you, Mein Fuhrer.”

There was also this: Hitler knew that the sight of thousands of bedraggled and defeated soldiers had demoralized the populations of Poland, Holland, Norway, and Belgium and helped to force their leaders to capitulate.

Even if Churchill gave the lion’s roar, Hitler may have thought the return of this beaten army could do his work for him. It could spare him the trouble and the risk of invading England.

For whatever reason, Hitler had ordered a halt for long enough for more thousands of the BEF to escape.

In the event, not just 100,000 soldiers returned to England, but 340,000.

Refusing to play the role of a defeated army, these grinning Tommies gave thumbs up all the way from their port of embarkation at Dover.

Churchill had to remind the British people that wars are not won by evacuations. True, but this doubter had to admit that this was a miracle of deliverance.