U.S. President Truman is faced with four options: peace talks (which would require the Japanese to keep their emperor, as eventually happened), a blockade (which was thought to be cowardly), an invasion (estimated by some to cost up to a million lives, though such numbers have been widely disputed), or dropping the bomb. Another consideration is that the USSR had said they would enter the war against Japan three months after the surrender of Germany and there is a fear that they might not leave. So Truman decides that the best course of action is to drop the bomb on Hiroshima, against the advice of General Eisenhower.