The U.S. killed more civilians in the firebombing of Tokyo than in the attacks on Hiroshima or Nagasaki. But nobody condemns them for that.
From Wikipedia:
https://en.wikipedia.org/wiki/Bombing_of_Tokyo
The US Strategic Bombing Survey later estimated that nearly 88,000 people died in this one raid, 41,000 were injured, and over a million residents lost their homes. The Tokyo Fire Department estimated a higher toll: 97,000 killed and 125,000 wounded.
And this from Wikipedia:
https://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki
In August 1945, during the final stage of the Second World War, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki. The two bombings, which killed at least 129,000 people, remain the only use of nuclear weapons for warfare in history.