Arthur T. Hadley said recently that those for whom the use of the A-bomb was “wrong” seem to be implying “that it would have been better to allow thousands on thousands of American and Japanese infantrymen to die in honest hand-to-hand combat on the beaches than to drop those two bombs.” People holding such views, he notes, “do not come from the ranks of society that produce infantrymen or pilots.” And there’s an eloquence problem: most of those with firsthand experience of the war at its worst were not elaborately educated people. Relatively inarticulate, most have remained silent about what...