Cold War (1985–1991) reduced some strategic arms unilaterally. Fundamental to the dissolution of the Soviet Union, the Gorbachev policy initiatives of Restructuring ("Perestroika") and Openness ("Glasnost") had ripple effects throughout the Soviet world, including eventually making it impossible to reassert central control over Warsaw Pact member states without resorting to military force. On June 12, 1987, Reagan challenged Gorbachev to go further with his reforms and democratization by tearing down the Berlin Wall. In a speech at the Brandenburg Gate next to the wall, Reagan stated: While the aging communist European leaders kept their states in the grip of "normalization", Gorbachev's reformist policies
Central Committee elected by the 27th Congress of the Communist Party of the Soviet Union by Gennady Kolbin, an ethnic Russian who had never lived in the Kazakh Soviet Socialist Republic. On 23 December 1985, the Politburo appointed Boris Yeltsin, an official from Sverdlovsk, First Secretary of the Moscow City Committee ("de facto" mayor of Moscow). Gorbachev had endorsed the appointment, heeding the advice of Yegor Ligachev (the party's informal second-in-command) who personally recommended him. In contrast, Nikolai Ryzhkov told Gorbachev in private that "He [Yeltsin] will cause you only grief. I would not recommend him." Yeltsin, who had introduced himself as something of a centrist at the 27th Congress, proved himself to be a