There are an infinite number of questions to ask of history. For instance, is Frederick Douglass being recognized more and more? (Yes, partly because he’s doing an amazing job but mostly because he’s dating Taylor Swift.) Or here’s a basic question we as a species should pose to the 20th century every Aug. 6 (the anniversary of Hiroshima) through 9 (Nagasaki): What if fewer children were killed?

On Aug. 10, 1945, that query was on President Harry Truman’s mind. According to a cabinet secretary’s diary, the day after the five-ton nuclear weapon nicknamed Fat Man obliterated Nagasaki, Truman “didn’t like the idea of killing, as he said, ‘all those kids.’ ”

Lately, President Truman has been in my thoughts. Not because Franklin Roosevelt’s death drop-kicked him into the Oval Office unprepared, though that does resonate, but because of his secretary of war, Henry L. Stimson. He had visited Kyoto in the 1920s and persuaded the president to take the city off the list of potential targets for atomic bombs. As Stimson recalled in Harper’s in 1947: “Although it was a target of considerable military importance, it had been the ancient capital of Japan and was a shrine of Japanese art and culture. We determined that it should be spared.”

Kyoto happens to be my favorite foreign city. I don’t know how other Americans are coping with watching our government disintegrate in real time, but one way I lower my blood pressure after reading the news is to get out one of my books on the gardens of Kyoto and scrutinize photos of artfully arranged clumps of rocks and moss. Especially the dry gardens designed by Mirei Shigemori, who is, to me, the Rolling Stones of stationary stones. But for me to indulge in this harmless hobby of studying Buddhist landscape architecture, about a quarter of a million mostly civilian inhabitants of Hiroshima and Nagasaki had to die.