What were the alternatives to the use of the atomic bomb? what were the pros and cons of each?

The alternatives was to continue to fight Japan or to abandon the fight sltogether. The pros of fighting Japan would be the avoidance of destruction of major Japanese cities and the death of innocent Japanese citizens, although it is likely that the Japanese would fight till their last citizen was killed. If America abandoned the fight with Japan, they would continue to be attacked, but countless innocent lives could be spared.

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