The men and women who brought down Adolph Hitler's war machine cannot defeat mortality. As the dwindling number of veterans who served during D-Day are saluted on the 70th anniversary, we might consider how different our lives might have been if those soldiers and sailors had been turned back from the beaches.
Stephen Ambrose, the American historian who founded the National World War II Museum in New Orleans, believed the Allies might have tried another invasion, when ocean tides allowed. But that would have meant another year of war and suffering, and it would have lacked the strength of surprise they had at Normandy.
Ambrose believed that the Churchill government would have fallen, and that Franklin D. Roosevelt might not have run for his fourth term. Isolationism, rampant on both the right and left in America and Britain before the war, would have been renewed. A Charles Lindbergh or Joseph P. Kennedy might have been elected in America to reach peace with Germany as Philip Roth imagined in his novel The Plot Against America. That would have left Germany free to pursue The Final Solution to extinguish Jews, gays, Roma and millions more from Europe.
John Keegan, the late British military historian, pointed out that Germany's V-1 rockets became operational just days after D-Day. "Large, static concentrations of shipping," he wrote, "present targets that could be devastated with ease," which would destroy any second invasion before it could launch.
The Allies might still have produced a nuclear weapon, as they did just a year after D-Day. But John Keegan reminded us, "Hitler ... had a nuclear weapons program of his own and ... might then have succeeded in threatening his enemies with a nuclear strike."
When we interviewed Mr. Keegan at his home years ago, he swept a hand over a globe and told us, "America would be marooned ... alone on a vast planet flooded by fascism."
Today we might ask: What kind of hell would we have grown up with, in a world commanded by the creators of the Nuremberg Laws and death camps?
The second world war animated a lot of Americans to live up to their ideals. The world began to overthrow empires, even as it struggled with totalitarianism, and America overturned segregation. As President Obama said Friday in Normandy, "None of that would have happened without the men who were willing to lay down their lives for people they'd never met and ideals they couldn't live without."
They were normal men and women, young, scared and vulnerable. That's what made them heroes.