 Complete the following phrase:  The Cold War period of 19851991 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 