" In January 1945, General Curtis LeMay arrived in the Mariana Islands to take over the problem-plagued B-29 command. For two months, his crews flew similar high-altitude missions over Japan with little more success. His job on the line, General LeMay decided on a risky new strategy: his pilots would fly daring, dangerous bombing missions at altitudes as low as 5,000 feet, low enough to be within range of anti-aircraft weapons. Robert Rodenhouse was shocked:
"We thought they could throw the kitchen sink up there and hit us. Can you imagine flying a big four-engine bomber at 5,000 feet? Why that was just unheard of, absolutely unheard of. And like my crew says, I think those generals lost their marbles. They weren't thinking straight."
The low-altitude bombing runs turned out to be highly successful. The planes carried much larger bomb loads. Crews flew at night to avoid enemy fighters. And flight personnel were kept to a minimum. Most of the gunners were removed to make room for still more bombs -- incendiary bombs."
https://www.pbs.org/wgbh/americanexperience/features/pacific...
What's the difference when the target is the civilian population, as was the case with the bombings of Japan (and many of the cities in the European theatre of the war as well)? Other than the fact bombing cities from a B-29 flying high is more impersonal for the perpetrators.