I would have to say that regardless whether the bombs were dropped on railyards, submarine bases, ball bearing factories or, on the general population, people were going to be killed either way. Surely there were humans at all those locations. The vast majority of the German people backed Hitler in the 1930s and up to 1945. To say the German population was unaware of the mass killings that the Nazis were inflicting upon the physically handicapped, mentally retarded, seniors, and not to mention the Jews, is ludicrous. Mass genocide was taking place, and it had to be stopped. Are we to turn a blind eye to what leaders of countries do to their own people?
Mao Zedong was responsible for between 34,000,000 to 68,000,000 deaths.
Stalin: 23,000,000 - 60,000,000 deaths
Hitler: 6,000,000 deaths
Hideki Tojo: 5,000,000 deaths
Pol Pot: 2,500,000 deaths
It's a shame those German cities were bombed. But, in the big scheme of things, I imagine the decision was made in order to break the will of the German people. And, I think it worked.