In December 1979, the Soviet Union invaded Afghanistan with tens of thousands of soldiers to back an insecure communist government facing rebellion. Afghanistan shared its southern border with the USSR, and the new regime in Kabul was considered an important bulwark against Islamic rebellions that Moscow feared might be building in Pakistan and Iran, the 1979 revolution in which the pro‑Soviet shah had recently been deposed
Cold War Objectives: It was an attempt by the USSR to keep Afghanistan within its sphere of influence and prevent Western or Islamic influence from reaching Central Asia.
The insurgency: Mujahideen guerrillas supported by some of the U.S., Pakistan, Saudi Arabia, and China conducted guerrilla attacks. Soviet helicopter gunships crashed through mountainsides; tunnel systems and cave complexes remained the rebels' stronghold.
Proxy War: America, fearing Soviet expansion, funded Stinger missiles and covert aid through the CIA's "Operation Cyclone," turning Afghanistan into one of the biggest proxy battlegrounds of the Cold War.
The Soviet withdrawal (1989): Following almost a decade of vicious to‑and‑fro with increasing Soviet casualties, Mikhail Gorbachev commanded a withdrawal.
Neither of them "won": The communist government remained in power for three more years but collapsed in 1992. Afghanistan then plunged again into civil war that facilitated the ascent of the Taliban to power.
Longer legacy: The war depleted Soviet funds and morale to the extent of leading to the dissolution of the USSR in 1991. It also created a generation of battle-hardened warriors later seen in local conflicts.