SURE, IT WAS only a game -- but if ever a pressure pump would set off the national juices, it was that impossible, super-upset of the ice age on Friday in Lake Placid. Here was your classic litter of mongrel underdogs -- puppies, yet -- romping off with a victory over the big bears who had pulverized everything in their path up till then. Decimating all odds and dazzling even themselves, this team of 20 youthful amateurs couldn't have produced a more welcome excuse for unabashed star-spangled euphoria.

Recent international troubles surely had much to do with it, but the purely athletic feat accomplished by the U.S. hockey team would have been cause enough in itself. The Soviet team -- holder of a 21-game winning streak in the Winter Olympics --suddenly had been knocked out of the winners' circle. For a few marvelous moments, at least, Americans who have been agonizing over energy shortages could revel in the overflow of adrenalin from the U.S. players. It proved enough to panic the topseeded Soviets, who suddenly witnessed a team they had trounced 13 days earlier tucking it to them.

The U.S. ecstasy does not stop at the ice rink, either. The whole world can marvel at another impossible feat by American Eric Heiden, who has broken world speed-skating records like eggs and shaken the gold market by winning an unheard-of five top medals. And how about Phil Mahre, the first American man to win an Alpine medal in 16 years -- a man who suffered a severely broken ankle on the slalom course last year and defied all medical opinion to capture a silver medal in the men's slalom this year?

From all this Americans can draw a rare upbeat message in this downbeat time: everything unexpected isn't bad.