There has lately been some questions about the U.S. getting into WW II earlier but the only way that I can see that it if Hitler and Germany engage in Absolutely Stupid Behavior. As I see it if Germany act aggressively at the outbreak of war by sinking U.S. flagged ships in International Waters, demanding that the U.S. cease trade with any countries that are at war with Germany, THEN if the U.S. refuses, Germany declares war against the U.S. From my limited understanding of the state of the U.S. Military at the time, the first thing is the U.S. would do is mobilize reserves and NG forces. The U.S. industry would go on war footing. The first effect I could see is that the U.S. would be sending is Trucks, trucks, and more trucks to France as soon as they roll out the factory doors. I did not realize how much France depended on horse drawn carriages to transport supplies, so if we stick the with OTL timeline, France and the BEF should be fully motorized by March 1940. I have learned on this site that France over mobilized at the start of the war and it hurt the production of weapons, so with the U.S. in the war, France and Great Britain do not have to mobilize as fast. I believe that the B-17 just became operational and with deployment to France, it would force Germany to keep more of it's fighters in reserve for defense. So when would the first U.S. troops be arriving to France, and would that force Germany to act faster? What about Belgium and the Netherlands, would they be more inclined to Allies side if the U.S. was involved?