The atomic bombs weren't needed to force a Japanese surrender. I believe Truman used the bombs as a show of force to the Soviets in pursuit of global supremacy. Japan had already been obliterated with the firebombing of Tokyo in March, 1945 -(Operation Meetinghouse) - 5 months before the dropping of the atom bombs. 300+ B-29s dropped napalm carrying incendiary bombs killing over 100,000 & destroying 15 square miles of Tokyo - the single deadliest air raid of WW2 - greater than either Hiroshima or Nagasaki. After the emperor saw the aftermath, peace negotiations were opened with the U.S. The Soviets also entered the war against Japan with the invasion of Manchukuo in August, 1945, also before the dropping of the atom bombs, and had Japan on the run & was a significant factor in Japan's surrender.
I had a great Uncle who was a bombardier in one of the B-29 Superforttesses that participated in Operation Meetinghouse. When I was in HS back in the 70s he would tell me how traumatic it was seeing most of Toyto engulf in flames & the destruction that followed. He didn't think the atom bombs were necessary. And recall Patton hated the Soviets more than the Nazis & was pushing for war with them after V-E day.
I think if Ukraine had succeeded in taking out Gerasimov it would have been a turning point in the war & would have exacerbated the already very poor moral within the Russian military.