 Complete the following phrase:  In the mid-1980s, the last Soviet leader, Mikhail Gorbachev, sought to further reform and liberalize the economy through his policies of glasnost and perestroika. The goal was to preserve the Communist Party while reversing economic stagnation. The Cold War ended during his tenure and in 1989, Warsaw Pact countries in Eastern Europe overthrew their respective Marxist-Leninist regimes. Strong nationalist and separatist movements broke out across the USSR. Gorbachev initiated a referendumboycotted by the Baltic republics, Armenia, Georgia, and Moldovawhich resulted in the majority of participating citizens voting in favor of preserving the Union as a renewed federation. In August 1991, 