The Cold War

The Cold War was a sustained state of political, military, economic, and ideological tension between two rival coalitions that dominated international affairs from roughly 1947 to 1991. On one side stood the United States and its Western allies, most of them organized in the North Atlantic Treaty Organization (NATO). On the other stood the Soviet Union and its satellite states, formally linked in the Warsaw Pact after 1955. The rivalry was rooted in incompatible visions of how societies should be organized: democratic capitalism and market economies in the West, and Soviet-style one-party communism and centrally planned economies in the East.

The conflict is called a "cold" war because the two superpowers never engaged each other in direct, large-scale combat. Instead, they competed through an enormous peacetime military buildup, nuclear deterrence, espionage, propaganda, economic pressure, scientific competition, and support for opposing sides in dozens of regional conflicts. These proxy wars, fought in Asia, Africa, Latin America, and the Middle East, were often extraordinarily violent and together caused many millions of deaths.

Historians debate where the Cold War should be dated from. Some begin it at the Yalta and Potsdam conferences of 1945, others with the Truman Doctrine speech of March 1947 or the Berlin Blockade of 1948 to 1949. Most agree that it ended with the collapse of the Soviet Union in December 1991, although some trace the symbolic end to the fall of the Berlin Wall in November 1989. Interpretations of who was primarily responsible for starting the Cold War remain contested among scholars, with traditionalist, revisionist, and post-revisionist schools offering different emphases.

The Cold War reshaped every inhabited region of the world. It drove decolonization in complicated directions, spurred the arms race and the space race, created new international institutions, fuelled civil wars, divided nations and families, and left a legacy of nuclear weapons, alliance structures, and unresolved conflicts that continues to influence twenty-first-century geopolitics.