How did the soviet invasion of afghanistan contribute to the fall of the soviet union?

Explanation:

It's true that the United States funneled military funding for weapons to the mujahideen, but that was typical for a Cold War conflict.  The significant reality that contributed to the collapse of communism in the Soviet Union was the fact that the mighty Soviet military machine no longer looked so mighty.  The Afghan resistance to Soviet-sponsored communism could not be overcome by the Soviet troops.  During the course of the decade-long conflict (from December 1979 until February 1989), approximately 15,000 Soviet soldiers were killed and another 35,000 wounded.

The Washington Post reported in 1988, after the USSR had been struggling in its war with the Afghans for nearly a decade: "Afghanistan is Russia's Vietnam -- possibly with even greater consequences for the Soviet Union."