Were The Russians Right To Have Invaded Afghanistan?

In 1979, the Soviet Union invaded and occupied Afghanistan in support of a puppet government they put in power, causing widespread death and destruction. The U.S. government was horrified and funded and armed the "freedom fighters" who fought the Soviets, "freedom fighters" now called Al-Qaeda and the Taliban.

As an additional sign of the U.S. government's condemnation of the Soviet's Afghan invasion, it boycotted the Moscow Olympic Games in 1980 and encouraged other nations to do so as well. In response, the Soviets boycotted the Los Angeles Olympic Games in 1984 as did many other nations under their influence.

The Afghanistan War, which then was often called "Russia's Vietnam," was the final straw that bankrupted the Soviet Union in 1989 and brought its collapse. Since 2001, when the U.S. overthrew the Taliban and put in its own puppet government, America has fought to keep it in power at a horrific price in lives and dollars. And the U.S. economy is sinking.

Why was it wrong for the Soviets to have invaded and occupied Afghanistan but not for the U.S. to do so? What can the Afghans or America and its allies possibly gain by this military occupation?

Dick
Note: This topic and the irony of the Olympic boycotts came from comments made by Stephen Colbert on the Colbert Report (1-20-11)