Notably, the treaty that ended World War I significantly shrank Germany's military, which wounded their pride. Economic hardships followed World War I but hit Germany particularly hard because its colonies were given to victorious nations. Inflation was devastating, throwing even people who had been well-to-do into poverty. All of this made Germans an easy target for someone like Adolph Hitler, who promised to return German to its deserved glory.

The "Cold War" that followed World War II resulted because the United States and the U.S.S.R. were uneasy allies during World War II. They united for a negative reason -- they were both opposed to Hitler's Germany.

After the war, however, the U.S.S.R. showed the same desire that Germany had prior to both world wars: they wanted to dominate Europe. They imposed Communist regimes on a number of weaker countries including Czechoslovakia, Romania and Bulgaria. The United States was adamantly opposed to any expansion of Communism, and both battled over control for Berlin.

The U.S.S.R. expanded its sphere of influence considerably, but the United States managed to check its spread. It forced a stalemate in Korea and checked the spread of communism into southeast Asia. The United States and the U.S.S.R. both acquired nuclear weapons, making war between the two countries unwise for both.
Ultimately Communism proved an unreliable economic system, and it has greatly diminished in influence, something that could be considered a United States triumph in the Cold War.

SOURCE

Author not given. 2003. "The Great War Effects," in IB History Pages. Accessed via the Internet 12/5/04. http://www.pvhs.chico.k12.ca.us/~bsilva/projects/great_war/effects.htm

Author not given. 2004. "The Causes and Effects of World War I," in World History. Studyworld Studynotes. Accessed via the Internet 12/5/04. http://www.studyworld.com/newsite/ReportEssay/History/WorldWars%5CThe_Causes_and_Effects_of_World_War_I-82.htm