The Soviet Union -- which then included Tajikistan, Uzbekistan and Turkmenistan -- invaded Afghanistan in 1979. Years of fighting followed until the Soviet forces withdrew in 1989.

The fight against the Soviets marked the beginning of the two-decade career of bin Laden, who came to Afghanistan to battle the Soviets with fellow Islamic warriors, called mujahedin, and is now the alleged leader of a terrorist organization taking refuge with the Taliban.

Russia has emerged as a leading opponent of the Taliban, helping to finance the lingering Afghan civil war by providing arms to opponents in the north of the country and urging joint action by other European powers against the regime. Russia fears a new wave of instability in the already unstable region in the wake of the terrorist attacks in the United States.

Russian leaders say they are already at war with bin Laden and forces they describe as his proxies in Chechnya, a predominantly Muslim region in southern Russia that is fighting for independence. They say Chechen rebels have been financed by bin Laden and other Islamic extremists, although wthout citing conclusive evidence.