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"
Anatoly Chernyaev the Soviet Union. He became General Secretary Gorbachev's foreign-policy advisor in 1986 and continued to advise Gorbachev when the latter became President of the Soviet Union. In 2004, Chernyaev donated his diaries from the Gorbachev period to the National Security Archive at George Washington University, which has published portions of them in English translation; according to the editor, "One can confidently say that every bold foreign policy initiative advanced by Gorbachev in the years 1985-1991 bears Chernyaev's mark on it." Since then, the National Security Archive has made available Chernyaev's diaries from 1972 to 1978 with an English translation of