A PERVASIVE sense of uncertainty is hanging in the air. There's a querulous atmostphere in this season of taking stock. The annual game of forecasting is less inviting than it has seemed in the past. Who wants to try to guess when the hostages might come home, or where the prime interest rate will be a year from now, or whether there will be another oil crisis in the spring?

The sense of the future is usually a reflection of the immediate past. A year ago, it would have seemed impossible that the American diplomats would still be in Iran a second New Year's Day. It seemed a good deal less than probable that Mr. Carter would actually be defeated, or that Mr. Reagan would be the winner. Those events -- the Iranian negotiations and the election -- are, of course, related, for the Iranian episode has come to symbolize the widespread opinion that the American sense of right and law have suddenly come to count for much less than they ought to.

Oddly, last year's economic forecasts turned out to be quite accurate -- oddly, because the route turned out to be an unexpected one full of bad scares. No one foresaw the close brush with financial panic in March, or the precipitous decline of the economy in the spring, or the astonishingly early recovery in the summer that has led to the unprecedently high interest rates now. But most of the year-end numbers are roughly where last January's estimates suggested. The economic forecasters must feel like travelers whose plane was hijacked in midflight, and whose bus from the airport narrowly missed a disastrous collison. They arrived at their destination on time, without a hair out of place -- but very apprehensive about the next leg of the journey.

The present uneasy state of the American mind has been developing for some time. Perhaps the gasoline lines in 1979 fed the impression that the country has been caught up by invisible and uncontrollable forces. Certainly, the inflation has contributed profoundly to the sense of erosion. Europeans tend to shrug off the Russian invasion of Afghanistan as irrelevant. But to Americans it seems an ominous indication that perceptions of the balance of power have shifted, and not to this country's advantage.

The present condition of this country's morale is accurately represented by the epidemic of predictions of a coming economic crash. It isn't rational, but it's real -- as you can see by running your eye over the current titles at any bookstore. But the latest surprise in the economy has been the astonishing strength of its recent growth. It is, in fact, proving far more resilient and productive than you think to listen to the endless talk about weakness, decline and collapse. But low morale creates its own reality.

The country elected Mr. Reagan because, perhaps, most people don't really like this view of themselves and their future. They are looking for another style of address. No politician, unfortunately, can cure the world of its regrettable habit of dumping unpleasant surprises on the people who inhabit it. rBut many politicians have managed to covey a conviction that intelligence and courage will count for more than whatever reverses the coming year sends.