What was the overall effect of American support in the North African and Italian
campaigns?

The Allied victory in North Africa destroyed or neutralized nearly 900,000 German and Italian troops, opened a second front against the Axis, permitted the invasion of Sicily and the Italian mainland in the summer of 1943, and removed the Axis threat to the oilfields of the Middle East and to British supply lines to

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.