Near the end of WWII Japan was near defeat. Germany had already surrendered. Russia was advancing on all German fronts to take back what was theirs and maybe a bit more. America was advancing on all fronts in the pacific. The end of the war seemed near.  

"How allied intelligence understood the situation at the time was detailed in a report to the American and British Combined Chiefs of Staff, made public in 1976:

"The increasing effects of sea blockade and cumulative devastation wrought by strategic bombing . . . has already rendered millions homeless and has destroyed from 25 percent to 50 percent of the built-up area of Japan's most important cities . . . . A conditional surrender . . . might be offered by them at any time . . . .”