Mikhail Gorbachev came to power in the Soviet Union on March 11, 1985, and the next day negotiations on nuclear and space-based weapons began in Geneva.
U.S.-Soviet relations took a turn for the worse with the Soviet's arrest of U.S. reporter Nicholas Daniloff, evidently for use as a bargaining chip in response to the August 30, 1986 arrest of suspected KGB agent Gennadiy Zakharov.