In an attempt to stabilize the turbulent political situation in Afghanistan, the Soviet Union sends 75,000 troops to enforce the installation of Babrak Karmal as the new leader of the nation. The new government and the imposing Soviet presence, however, had little success in putting down antigovernment rebels. Thus began nearly 10 years of an agonizing, destructive, and ultimately fruitless Soviet military intervention in Afghanistan.
Ironically, Karmal overthrew and murdered another Afghan communist, Hafizullah Amin, to take power. Amin's government became unpopular and unstable after it attempted to install a harsh communist regime, declared one-party rule and abolished the Afghan constitution. Muslims in the nation rejected his rule and formed a rebel force, the Mujahideen. When it became apparent that Amin could not control the rebellion, Soviet troops intervened and put a puppet ruler, Karmal, into power. For the Soviets, political turbulence in this bordering nation, which was viewed by some officials as a potentially useful ally pursuing its interests in the Middle East, was unacceptable.
The Soviet intervention cost Russia dearly. The seemingly endless civil war in Afghanistan resulted in thousands of Soviet dead and untold monetary costs. It also brought an abrupt end to the era of détente between the United States and the Soviet Union that began during the Nixon years. In response to the Soviet intervention, President Jimmy Carter withdrew the SALT II agreement from consideration by Congress. The treaty, which had been signed in June 1979, was designed to establish parity in nuclear delivery vehicles between the United States and the Soviet Union. Carter also halted grain shipments to the Soviet Union and ordered a U.S. boycott of the 1980 Olympics that were to be held in Moscow.