Yes, it was necessary to stop the war.
The atomic bomb on Hiroshima was brutal, yes. On the other hand, it was the only way to stop the war. Japan was going to invade the U.S. and we were running out of supplies, people, guns, bullets, etc. It was either the bomb or lose the war. World War II was the fight for humanity, if Hitler won (not to be taken offensively) the world would have gone to hell.