The Cold War period of 1985–1991 began with the rise of Mikhail Gorbachev as General Secretary of the Communist Party of the Soviet Union. Gorbachev was a revolutionary leader for the USSR, as he was the first to promote liberalization of the political landscape (Glasnost) and the economy (Perestroika); prior to this, the USSR had been strictly prohibiting liberal reform and maintained a command economy. The USSR, despite facing massive economic difficulties, was involved in a costly arms race with the United States under President Ronald Reagan. Regardless, the USSR began to crumble as liberal reforms proved difficult to handle and capitalist changes to the economy were badly instituted and caused major problems. The Cold War came to an end when the last war of Soviet occupation ended in Afghanistan, the Berlin Wall came down in Germany, and a series of mostly peaceful revolutions swept the Soviet Bloc states of eastern Europe in 1989.