Here is Lt.-Col. Jim Stewart one month after the D-Day landings. I chose this image for the cover of Mission because it reflects the toll of war on a man so recently thought of as youthful. He had by this time flown 14 combat missions, earned two Distinguished Flying Crosses, and supervised his bomb group’s D-Day bombing missions. The photo was found in Jim’s personal collection, which he had donated to Brigham Young University.

One of my favorite chapters in Mission: Jimmy Stewart and the Fight for Europe concerns the run-up to D-Day, which Maj. Jim Stewart had a hand in, as did just about everyone in the Eighth Air Force. I well remember sitting in a Brigham Young University library looking at records from the 453^rd Bomb Group at Old Buckenham and feeling chills along my spine as I read a rare history of the 453^rd written during the war. It described “invasionitis”—the endless speculation over when and where the attack would take place—as it reached its peak, and then suddenly, after weeks and months of anticipation, the base went on lockdown. No one in or out. All leaves cancelled. No phone calls. All fliers on alert. Imagine how those guys felt—the invasion of Europe was at hand. It was Zero Hour, and they were literally on the front lines.

Now I’m researching my next book and looking at the impending invasion through the eyes of civilians in Nazi-occupied countries. As they felt the iron fist of Hitler’s Germany close around their throats, as Jews were sent away and innocent civilians were executed in reprisal for partisan raids, as young men and women were kidnapped off the streets where they’d lived all their lives and sent to Germany as slave labor or worse, the only hope of entire populations was an Allied invasion. Every day and every day and every day they waited and hoped and prayed, and it kept not happening. On the continent as in England and the U.S., rumors filled the vacuum of information as top-secret preparations continued. Loose lips could do a lot more than sink ships in May 1944—loose lips could result in a repulsed invasion and a prolonging of a war that had already killed tens of millions of human beings.

The landing craft that the B-24s couldn’t see as D-Day commenced.

Seventy-three years ago right now as I sit here in the New York time zone, B-24s took off from Old Buck to hit targets immediately behind the beach code-named Omaha on the Normandy coast. Jim Stewart briefed his bomber crews that they would be able to look down and see the mightiest fleet ever set to water, but upon return hours later, the pilots and bombardiers complained bitterly to Stewart that they had seen nothing because of heavy cloud cover. Among the things they didn’t see during those early June 6 sorties were their targets (Wehrmacht barracks and gun emplacements), which the bombardiers missed, and badly. Eisenhower had ordered a ‘Go’ to the operation despite continued lousy weather, and so shortly after dawn, tens of thousands of young men hit beaches that were supposed to be neutralized by bombing but hadn’t been softened at all. We know the result: Omaha was a bloodbath.

As the years pass by and the veterans of that day’s assault pass to glory, it becomes increasingly difficult to appreciate the gravity of D-Day, the shock of the headlines, the importance of the news to simply everyone in the world: to soldiers throwing up in landing craft in heavy seas knowing a storm of lead awaited; to parents across the ocean fearing for their sons in harm’s way; to oppressed civilians in France, Belgium, and the Netherlands desperate for liberation; to Jews heading for concentration camps or already there; and, yes, to Germans who could see their empire and dreams of a unified Europe slipping away. They knew that if the Allies got a foothold in France and headed toward Germany on one side with the Russians moving in on the other, the Reich was doomed.

For Baby Boomers (defined broadly as the children of service men who returned from WWII), D-Day is represented by The Longest Day, made by Darryl F. Zanuck’s 20^th Century Fox in 1962 over the course of 10 months at more than 30 locations in France. It’s an occasionally brilliant, mostly ham-handed, decidedly G-rated version of a brutal 24 hours in world history. If anything, The Longest Day trivializes what really went on as it lays on globs of irony that’s supposedly clever and amusing and gives us some of the more unusual casting in Hollywood history. Everybody who was anybody got a cameo to the detriment of what this epic picture might have been. Even 18 years after the event when The Longest Day was released, there was no way to convey what D-Day meant to the world. So many decades after that, it’s downright impossible to do justice to this day and these people on all sides, particularly all those men who stormed the beaches code-named Juno, Sword, Gold, Utah, and Omaha. All I can say is, I salute each and every one of them for what they gave the world—a chance for an end to the most catastrophic war in history. And beyond that, a chance for a peace in Western Europe that remains to this day. Stated plainly, the accomplishments of the men of D-Day will always dwarf any and all acts of terror, for it infused the continent with a steely resolve that I’m convinced will endure forever.

John Wayne and a bunch of guys who looked nothing–NOTHING–like the generation of young Americans who participated in D-Day. Press materials noted “an unusually large and attractive cast.” Um, agree about the large part, at least in the Duke’s case.