Why did the american soldiers invade Normandy in WW2?

The D-Day invasion took years of planning.

Allied leaders Franklin Roosevelt and Winston Churchill knew from the start of the war that a massive invasion of mainland Europe would be critical to relieve pressure from the Soviet army fighting the Nazis in the east.

this means that germany had to pay the allied countries. reparations are/is essentially payment for something that they have done wrong, so after ww1, germany was forced to pay reparations so they could replenish the allied countries resources' that they had lost during the war.

porter is writing economic history because he is focusing on the cost of developing vaccines.