This is what the Rev. George Zabelka, the Air Force chaplain who blessed the bomb on Hiroshima and Nagasaki, said:
As a Catholic chaplain I watched as the Boxcar, piloted by a good Irish Catholic pilot, dropped the bomb on Urakami Cathedral in Nagasaki, the center of Catholicism in Japan.
I never preached a single sermon against killing civilians to the men who were doing it… It never entered my mind to protest publicly the consequences of these massive air raids. I was told it was necessary – told openly by the military and told implicitly by my Church’s leadership.
Dating Jesus 
He blessed a bomb? Seriously? This reminds me of that good old saying: “Kill a commie for Christ.” People still say that we needed to drop the bomb in order to end the war, and maybe that is so. I wonder if the good Father also said a private prayer for the people who were killed, injured, rendered homeless and sick from that blessed bomb.
He spoke about his experiences quite a lot. He became a dedicated peace activist in his later years.