Most importantly, the Harlem Renaissance instilled in African Americans across the country a new spirit of self-determination and pride, a new social consciousness, and a new commitment to political activism, all of which would provide a foundation for the Civil Rights Movement of the 1950s and 1960s.
Passage of the Lend-Lease Act represented a shift from the foreign policy that dominated American politics between the two world wars. Prior to its passage, the US followed a policy of isolationism and remained out of affairs. The Lend-Lease Act led to the US's supplying of Great Britain with arms, foodstuffs, and ships for war.
Knowing the terrain gave the Americans an advantage because they were familiar with it and knew their way around. Here are some links for additional information:
https://historyofmassachusetts.org/how-did-geography-influence-boston-battles/
https://www.khanacademy.org/humanities/ap-us-history/period-3/apush-the-american-revolution/a/apush-the-american-revolution-lesson-overview
