This is incorrect on a number of fronts: 1) The Japanese surrender was unconditional. The emperor's positions as very much at Douglas Macarthurs will. (And this was made clear before the surrender). 2) There was no move to cut the soviets out. Stalin immediately became paranoid (as he often did) and moved up his time frame once it became clear (before Trinity) that the USA would have the bomb soon. 3) Truman never decided any such thing - in fact, he announced ("with glee" according to the reporters present) that Stalin had entered the war. This narrative comes from Hasegawa's book, and it's completely incorrect.