I can't think of one. Given the circumstances and the time in which the game happened, this one wins in a landslide. The Americans taking down the big bad Russians during the Cold War. Sucks I was a mere two years old then.
The Russians had killed us at MSG not too long before that game too. All the **** going on in the world then too. The Iranian Hostage Crisis, our economy was in shambles, the Russians were invading Afghanistan, etc.
Considering the game we beat the Russians was NOT the gold medal game, I would not say it was America's biggest sporting moment. I would go with Jesse Owen's four gold medals at the 1936 Olympics in front of Hitler.