Can I pose this question?............

If you were the American C in C, with complete control in the campaign against Japan, would you A.... continue the blockade and bombing for as long as it took to force surrender [B-29 casualties in the last series of raids was 0.9%,] or B....invade to try and finish the war sooner and take up to a million casualties?

Naturally this is on the proviso that the bombs didn't force surrender.