His outfit was bombing Frankfurt, and the plane was hit by anti-aircraft fire over the German city. I don't know more details, except it was reported that he kept trying to keep the plane flying, so the crew could parachute out, which some, but not all, were able to do. Clay had a newborn son. They'd be knocking on our door. I wasn't alone.
Short answer is yes, it had to be done.
If we would not have done that, they would have controlled all of Europe, all of Asia, likely Australia, and perhaps Africa. Then they would have moved in on South America. And so forth. Forty to 60 million people were killed, mostly civilians, so a high price was paid. Maybe we, meaning Allies, could have been smarter before the war began, and not let Hitler and Hirohito get such a rolling start.