Yes, that was the driver. We knew they were trying to build such a device, but we didn't know how far along they were. Given the German lead in other war technology areas (like guided missiles), it would have been foolish to underestimate them.
Of course the Germans were lucky to have lost before the bomb was ready. Otherwise instead instead of memorials at Hiroshima and Nagasaki they might be at Munich and Hamburg.
Of course the Germans were lucky to have lost before the bomb was ready. Otherwise instead instead of memorials at Hiroshima and Nagasaki they might be at Munich and Hamburg.