President Roosevelt had died, and Truman became president. He learned of the atomic bomb and its power. Meanwhile, American soldiers had gone far into Germany while Hitler's army was collapsing. They found out that the Germans were far from completing an Atomic bomb, which relieved many, but now there was the matter of keeping the Soviets from building a bomb.
Harry Truman, the new president
Gold was sent on a side mission to retrieve information from Fuchs and Greenglass, and eventually to Yatzkov to give him the reports.
As the scientists at Los Alamos finished their bombs, they questioned the necessity for testing them. Groves did not want to, because it would be a waste of plutonium, but Oppenheimer convinced him that it was very important that they test the bomb.
As they got closer and closer to the testing date, Oppenheimer and his team worked tirelessly to fix the problems that erupted every day. Eventually they had everything set up and ready to go, but the weather did not allow them to detonate the bomb, and so they waited.