With massive quantities of weapons and tanks from World War II, and the factories to produce them, the Russians exported them and built up client states which spread their influence and became involved in the continuing state of political conflict, military tension, proxy wars, and economic competition existing afterwards known as the Cold War. The Cold War featured periods of relative calm and of international high tension – the Berlin Blockade (1948–1949), the Korean War (1950–1953), the Berlin Crisis of 1961, the Vietnam War (1955–1975), the Cuban Missile Crisis (1962), the Soviet–Afghan War (1979–1989), and various smaller conflicts in which Soviet weapons had significant impact in many wars.