A rose laid at a headstone at Arlington National Cemetery May 28. (Aaron P. Bernstein/Getty Images)

“THEY DIED for you.”

That is a stark and powerful truth about lives lost in the nation’s wars, rarely stated so plainly as it was in an essay that appeared on these pages eight years ago by historian Rick Atkinson. His topic was 10 things Americans ought to know about World War II, on which he has written extensively. Undoubtedly the most striking to many readers was the last, which began with the words quoted above.

“The U.S. military sustained almost 300,000 battle deaths during the war, and about 100,000 others from accidents, disease, suicide,” Mr. Atkinson wrote. “Many of those deaths were horrible, premature, and unspeakably sad. . . . The most critical lesson for every American is to understand, viscerally, that this vast host died one by one by one; to understand in your bones that they died for you.”

They didn’t die as willing martyrs, and most didn’t consider themselves heroes. They simply did what was expected of them, including those who were conscripted. The lives of those who served were disrupted, their futures often diminished — and many never came back. They were mostly ordinary people who accepted it as their duty and obligation to face the dangers of war.

This Memorial Day you might want to read some of the collections of letters home from war fronts that are available on the Internet. They are filled with gripes about food, fears and discomforts, but more importantly with words of reassurance to loved ones and above all a constant longing to be home again, to have this over with. Only occasionally do they deal with the ultimate disturbing realities of the war, as in this letter from a Chicago soldier to his parents in 1944 (complete with a few misspellings):

“I recently was able to see some of the dead boys they had just taken off the battlefield. . . . When you look at them you can’t help but think--why are they dead! Just a year or so ago they were either going to school-working-married and now their dead. Many among them had ambition--all looked forward to the future--Now their dead. It keeps shooting thru your mind-again and again-why have these men died? I know why we fight-I know of the values we’re trying to secure. I hope these men have not given their lives for empty words.”

The country has lost thousands of men and women in the armed conflicts of this still-new century, and many Americans ask the same questions and harbor the same doubts as did that Chicago soldier. The only certain thing is that they died for us: Individual human beings died in our place when the country called on them. In a time when personal self-aggrandizement seems to be in vogue for far too many, we need to give more thought and attention — and thanks — to those who exemplify selfless service.