The U.S. emerged as a leading superpower and the sole nuclear power in the world, determined to play a leading role in international politics. The post-Second World War era saw the start of a prolonged Cold War in which the U.S. competed for political domination around the world with Soviet Communism until the collapse of the Soviet Union in 1990. The Second World War also helped the country to overcome the economic depression of the 1930s as its wartime industrial production stimulated its economy. References

Arima, Y. (2003). "The Way to Pearl Harbor: U.S. Vs. Japan." ICE Case Studies:

Number 118, December, 2003. Retrieved on May 26, 2007 at http://www.american.edu/TED/ice/japan-oil.htm

Dwyer, J.J. (2004). "The United States and World War I." Lew Rockwell.com. Retrieved on May 26, 2007 at http://www.lewrockwell.com/orig3/dwyer3.html

Keylor, William R. (2007). "World War I." Encyclopedia Encarta Online. On May 26, 2007 at http://encarta.msn.com/encyclopedia_761569981/World_War_I.html

Steiner, Z. (2001). 2 the Treaty of Versailles...

In the Paris Peace Conference, 1919: Peace without Victory? (pp. 13-33). New York: Palgrave.
WWI was fought between the Allied Powers (the U.K., France, Belgium, Serbia, Montenegro, Japan, Italy, Russian Empire and the U.S.) and the Central Powers (the Empires of Germany and Austria-Hungary, the Ottoman Empire and Bulgaria), while the WWII involved Allies (Britain, France, Soviet Union, and the U.S.) and the Axis powers (Germany, Italy, and Japan)

Some historians have even gone to the extent of terming WWII as an extension of the First World War

British passenger liner Lusitania was sunk by the Germans on May 7, 1915, killing 128 Americans; several American ships were sunk in February and March 1917

In addition, President Roosevelt and Prime Minister Churchill had developed close personal relationship

The program of "cash and carry" served a two-pronged purpose -- it helped the U.S. economy that was emerging from a pro-longed economic depression and assisted the Allies in their war effort against Germany

WWI & WWII