The world's most dangerous summer

Seventy years ago this summer, the Western democracies faced what may have been the most dangerous moment in their histories. We tend to be fascinated by turning points - those decisive moments when the fate of nations is at stake. June through September of 1940 was just such a moment.

In a matter of six weeks, Adolf Hitler's armies - which had already dispatched Poland in a month - swept through Belgium, Holland, and France. France, which had defied Germany for four years in World War I, was effectively beaten after six weeks, in June 1940. Hitler dictated the ignominious terms of surrender in the same railway car that was the setting for Germany's defeat in November 1918.

For the Western democracies, all seemed lost. Only Great Britain, which had been driven off the European continent at Dunkirk, stood between Germany and complete domination of Europe.

That this domination did not occur was the result of a series of decisions, incidents, and actions that summer that ultimately brought about the defeat of Germany and the emergence of the United States as a world power.

First, and in some ways foremost, was the determination of one man: Winston Churchill.

In July, Hitler offered Britain peace terms that were tempting: In return for recognition of German supremacy in Europe, Germany would leave the British fleet and empire alone.

Distrusting Hitler, Churchill and his cabinet (despite some waverers) never seriously considered these terms. On July 3, in case Hitler had any doubts as to Churchill's resolution, the British navy sunk the fleet of its former ally France at the port of Oran, Algeria, lest it fall into the hands of the Germans.

From that point, the situation slowly began to improve for Britain.

In one of the speeches that had bonded him to the British people that spring, Churchill had thrown down the gauntlet:

"Hitler knows he will have to break us in this island or lose the war," he said. "If we can stand up to him, all Europe may be free, and the life of the world may move forward into broad, sunlit uplands. But if we fail, then the whole world, including the United States, including all we have known and cared for, will sink into the abyss of a new dark age made more sinister, and perhaps more protracted, by the lights of perverted science."

Hitler failed to break England and lost the Battle of Britain that summer. It was the first setback he had experienced in his campaign of conquest.

Fateful decisions flowed from that defeat. Hitler's threat to the West clinched President Franklin D. Roosevelt's determination to run for an unprecedented third term, which he wouldn't have considered if the world had been at peace. Roosevelt's decision proved crucial because, according to a Gallup poll that summer, Americans were suffering from a split personality: They were sympathetic to England but wanted to remain neutral in the war.

Nevertheless, FDR began - hesitantly at first - to take a series of steps to aid Great Britain in the war. He surreptitiously shipped infantry weapons, ammunition, and airplane parts to England. More importantly, in September, the United States signed the Destroyer Deal with Britain, whereby 40 American destroyers were exchanged for British bases in the Caribbean - the first of many decidedly un-neutral American acts, and the beginning of the United States' becoming, as Roosevelt put it, the "arsenal of democracy."

An even more significant decision was made that summer as a result of Hitler's failure to impose his will on Britain. In July, the month the Battle of Britain began, Hitler for the first time expressed his determination to attack the Soviet Union, until then an almost obsequious ally of Germany.

When, by autumn, it became clear that Britain hadn't been knocked out of the war, Hitler ordered a bombing campaign - the Blitz - as a way of neutralizing any threat from her. That enabled him to turn his full attention to the Soviet Union. That October, he issued Fuhrer Directive 21, "Operation Barbarossa," - the plan to attack the Soviet Union in the spring of 1941.

Hitler figured Great Britain would not be strong enough to interfere with his plans, and that the United States was a corrupt mongrel nation that he could leave to the attention of his ally Japan.

Thus, like Napoleon before him, Hitler miscalculated by striking east against Russia before removing the threat of Britain from the west. And he suffered a fate similar to Napoleon's.

All of this flowed from Hitler's great failure in that dangerous summer of 1940 - his inability to impose his will on Churchill and Britain.