How did it lay the groundwork for the conflict with america in world war ii?

How did what lay the groundwork???
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World War II was the largest and most violent armed conflict in the history of mankind. However, the half century that now separates us from that conflict has exacted its toll on our collective knowledge. While World War II continues to absorb the interest of military scholars and historians, as well as its veterans, a generation of Americans has grown to maturity largely unaware of the political, social, and military implications of a war that, more than any other, united us as a people with a common purpose