the National Museum of the U.S. Navy in Washington, D.C., states unambiguously on a plaque with its atomic bomb exhibit: “The vast destruction wreaked by the bombings of Hiroshima and Nagasaki and the loss of 135,000 people made little impact on the Japanese military. However, the Soviet invasion of Manchuria … changed their minds.”
Seven of the United States’ eight five-star Army and Navy officers in 1945 agreed with the Navy’s vitriolic assessment. Generals Dwight Eisenhower, Douglas MacArthur and Henry “Hap” Arnold and Admirals William Leahy, Chester Nimitz, Ernest King, and William Halsey are on record stating that the atomic bombs were either militarily unnecessary, morally reprehensible, or both.
“that the use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender …. In being the first to use it we had adopted an ethical standard common to the barbarians of the Dark Ages.”
“the Japanese were ready to surrender and it wasn’t necessary to hit them with that awful thing.”
https://www.latimes.com/opinion/story/2020-08-05/hiroshima-anniversary-japan-atomic-bombs