A negotiated peace would have left the old Japanese political and social structure in place that could possibly start another war later. The bomb was meant to win the peace as well as the war. I hate to think what the Russians would have done if they took over Japan, which might have happened while we were trying to negotiate this peace. Dropping the bomb was the right thing to do. It saved a lot of American and Japanese lives. The left needs to stop whining about it.
The Russians would have kept the bulk of the rabid militarist army and navy principals intact under their control.