History of socialism under challenge from Solidarność, or Solidarity, a labor union under the leadership of Lech Wałęsa. The union was sufficiently threatening to the government that on 13 December 1981, the head of state, Wojciech Jaruzelski declared martial law, suspended the union, and imprisoned most of its leaders. Mikhail Gorbachev (born 1931), who took control in 1985, was the first Soviet leader to have been born after the October revolution. He is remembered for three initiatives: "glasnost", "perestroika", and the "Frank Sinatra doctrine". "Glasnost", or "openness", was Gorbachev's term for allowing public debate in the Soviet Union to an unprecedented degree. "Perestroika"
Mikhail Gorbachev carried out only personnel shifts rather than structural change. Andropov encouraged Gorbachev to expand into policy areas other than agriculture, preparing him for future higher office. With Andropov's encouragement, Gorbachev sometimes chaired Politburo meetings. In April 1983, Gorbachev delivered the annual Lenin's birthday speech; this required him re-reading many of Lenin's later writings, in which the first Soviet leader had called for reform, and encouraged Gorbachev's own conviction that reform was needed. In May 1983, Gorbachev was sent to Canada, where he met Prime Minister Pierre Trudeau and spoke to the Canadian parliament. There, he met and befriended the Soviet