structural:scholar_edition, linguistic:paraphrasing, structural:expansion
The end of the Cold War

During the mid-1980s, the U.S-Soviet relations significantly improved, Mikhail Gorbachev assumed control of the Soviet Union after the deaths of several former Soviet leaders and announced a new era of "perestroika" and "glasnost," meaning restructuring and openness respectively. Gorbachev proposed a 50% reduction of nuclear weapons for both the U.S and Soviet Union at the meeting in Reykjavik, Iceland in October 1986. However, the proposal was refused due to disagreements over Reagan's SDI. Instead, the Intermediate Nuclear Forces (INF) Treaty was signed on December 8, 1987, in Washington, which eliminated an entire class of nuclear weapons.

Owing to the dramatic economic and social changes occurring within the Soviet Union, many of its constituent republics began to declare their independence. With the wave of revolutions sweeping across Eastern-Europe, the Soviet Union was unable to impose its will on its satellite states and so its sphere of influence slowly diminished. By December 16, 1991, all of the republics had declared independence from the Union. The Soviet leader, Mikhail Gorbachev resigned as the country's president on December 25 and the Soviet Union was declared non-existent the following day.