Every August 6 this comes around, and I have to give my take. No, the atomic bombs were not controversial and were entirely justified. Totally justified. When Japan was already being starved and firebombed, when the bloodbath of Okinawa was fresh in sight, to not use the superweapons would be wrong even by 2020s standards, much less 1940s ones.
Were they horrific? Definitely. Were they a magic win button that guaranteed a peaceful surrender in place of an invasion that could have killed a million Americans and ten-twenty times as many Japanese? Not by themselves. Could you have wished the war would have ended without them? Of course.
But there was no way they were not being used, and they very well could have prevented something worse. Much worse.