The story is now becoming familiar in repetition.

Americans are told they are facing some major threat to their national existence - their very way of life. But when the chips are down it turns out the much-feared enemy was a paper tiger. We didn't understand him.Saddam Hussein is just the latest in a long series of examples.

Certainly Saddam has proven to be a tiger to his own people, but on the battlefield he was a pussycat.

Army Gen. H. Norman Schwarzkopf has acknowledged that Americans vastly overestimated the size of Saddam's army. Intelligence reports said allied forces faced at least half a million Iraqi troops in Kuwait and southern Iraq. Schwarzkopf says it turned out to be no more than 300,000, maybe not that many.

Despite billions of dollars spent on sophisticated spy satellites, American intelligence agencies couldn't even come close in estimating the opposition. They were off by hundreds of thousands - by whole divisions.

More than that, Saddam's troops wouldn't fight. The problem on the battlefield didn't turn out to be his tanks, or his land mines or his poison gas - dangers we were endlessly warned about.

The problem turned out to be how to handle the vast numbers of his troops who were trying to quit.

Any general will tell you that the will to fight can be the most critical factor in war. Our intelligence agencies missed in assessing this factor, too.

Nor did anyone in the American government foresee that Saddam might turn on his own people after the cease-fire, driving hundreds of thousands from their homes, creating a massive human catastrophe for refugees.

"Are you asking me if I foresaw the size of the Kurdish refugee problem?" President Bush said to a reporter Tuesday. "The answer is, no, I did not."

The United States spends more than $30 billion a year on intelligence - the figure is still classified. Why did we know so little? How wrong can you get?

Intelligence misjudgments about Saddam Hussein, however, are simply the most recent chapter in what is now becoming a long, sad commentary.

Before Saddam came the mighty Russians. Year after year, for 40 years, Americans were told about the Russian threat. They spent trillions of dollars to counter it.

Pentagon intelligence estimates were warning of the dangers of possible Soviet attack well into 1989, when suddenly the whole communist apparatus began to fall apart.

The experts had missed the biggest story of all - that the communist system would collapse from within.

Somehow they could only see Soviet military strengths and theoretical capabilities. They could not see its political and economic weaknesses.

Today the Soviet Union is a hollow shell that is falling apart. The experts counted all those Soviet weapons, but failed to discern a massive historic trend that has left the communist system in ruins.

There are other, less cosmic cases, too.

Presidents of both political parties told us a communist victory in Vietnam would touch off a "domino" effect that would sweep through Asia. President Johnson once said San Francisco would be threatened if the North Vietnamese won the war.

Well, the North Vietnamese won and somehow Thailand and Burma and Singapore are still there and still non-communist. There was no "domino" effect. San Francisco seems safe.

Something is seriously wrong here. Our best and our brightest have not been able to assess correctly the real challenges we face. Our multi-billion dollar super-secret intelligence systems have failed us miserably.

They have seemed repeatedly to undervalue our own system and our own successes, and to exaggerate the capabilities of others in different cultures.

It is not that we have lacked legitimate enemies or had many legitimate concerns. The record suggests, however, that we have had a tendency to make giants out of some very troubled pygmies.

Why have our experts been so wrong so often?

This is a basic question that should be asked in Congress and by the administration, but isn't being asked. The tendency by both is to reason that if we won the war against Saddam, and we won the Cold War, we must be doing something right.

Well, we are. But now we know that Saddam was a pushover, a phony. So were the Russians. Neither was the threat we were warned about.

How did we come to believe so passionately that they were?