Among the major publishing events of the summer is “The Greater Journey: Americans in Paris,” in which widely popular historian David McCullough chronicles the many Americans who visited the City of Lights between 1830 and 1900, returning to the United States with fresh ideas about art and medicine, literature and life at large. McCullough’s book promises to be a staple on the bestseller list this season, a timely reminder of the deep ties that have connected our nation and France since the American Revolution.

Today, June 6, should be a day to remember a particularly important moment in that relationship — the June 6, 1944, Allied invasion of Normandy, famously known as D-Day. The invasion, led by Gen. Dwight Eisenhower, was necessary to liberate France from Nazi Germany, and the invasion was the beginning of the end of World War II in Europe.

The liberation of France came at an awful cost, with at least 2,500 Allied soldiers dying during the D-Day operation. Some newer estimates place the death toll even higher.

Writer William Zinsser, a World War II veteran who visited the American military cemetery near the site of the invasion, was struck, in reading the tombstones, about what he saw:

“The date June 6, 1944, recurred with terrible frequency; for many of those young men, their first day of combat was also their last.”

Today is a day to remember those young men, and the comrades who survived them, some of whom are still with us.