This is a line of argumentation that a lot of Catholics don't like to hear, because they want to support the end of the Pacific front in World War II, but we need to hear it and discuss it - because applying Catholic teaching must come before being an American. I am not saying that you MUST agree. But, I am asking you to prayerfully consider what Jimmy has to say. A snip:
That means that, even if Hiroshima and Nagasaki had contained military resources that of themselves would have justified the use of atomic weapons (which is very hard to argue), our intention still was not pure. We were still using Japanese civilians as hostages to the war effort, still threatening to kill civilians if Japan did not surrender. That was the message we wanted the Japanese leadership to get—not, “We will take out your military resources if you keep this up,” but, “We will take out big chunks of your population if you keep this up.”
That meant that the U.S. leadership was formally participating in evil. It does not matter if the attacks of Hiroshima and Nagasaki could (through some stretch of the imagination) be justified in themselves. The fact is that they were used to send a message telling the Japanese government that we would kill massive numbers of the military and civilian population, without discrimination. That message is evil, and to knowingly and deliberately send that message is to formally participate in evil.
That made these attacks war crimes.