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"
Communist Party of the Soviet Union became leading officials under Gorbachev. Andropov supported increased openness in the press, particularly regarding the challenges facing the Soviet Union. Andropov was in office briefly, but he appointed a number of reformers, including Yegor Ligachev, Nikolay Ryzhkov and Mikhail Gorbachev, to important positions. He also supported a crackdown on absenteeism and corruption. Andropov had intended to let Gorbachev succeed him in office, but Konstantin Chernenko and his supporters suppressed the paragraph in the letter which called for Gorbachev's elevation. Andropov died on 9 February 1984 and was succeeded by Chernenko. Throughout his short leadership, Chernenko was unable to consolidate power