The Cold War, the defining conflict of the post-WWII world, was a period of hostility between the Western Bloc, consisting of the US, Western European countries like the UK and France, and their allies, and the Eastern Bloc, consisting of the Soviet Union, its satellite states, China, and their allies. The conflict was primarily ideological: the free-market capitalism of the West versus the socialism of the Eastern Bloc. It was called a “cold” war because there were no major military clashes between the two sides; however, each supported opposing sides in regional conflicts. These were known as proxy wars. A pervasive fear at the time was that the war going “hot” would result in a devastating nuclear arms exchange. Though the Cold War never spilled over into open conflict, its tensions led to massive military spending and nuclear proliferation and had a massive impact on the culture and policies of the West, as well as many other regions throughout the world.

The Cold War officially ended with the fall of the Berlin Wall in 1989, but the collapse of the Soviet Union in 1991 is often considered its true ending. With the collapse of its primary rival, the Western powers, particularly the US, found themselves in a world with no ideological opponent and at the height of their power.