You would be hard-pressed to find anyone in Washington last week talking about a balanced budget amendment not with new projections showing that the federal deficit is shrinking to its lowest level in more than 20 years.

Thanks to the economy’s amazingly robust performance evidenced by 5.6 percent growth in the first quarter tax receipts are expected to be $25 billion higher than expected. That will help bring down the deficit to $75 billion, lower than even White House officials would have dreamed just 12 months ago.

As Washington’s pundits and politicos scramble to explain away such a phenomenon, they might start off admitting that they had nothing to do with it.

It’s the marketplace, stupid. It wasn’t tax cuts that shored up the government coffers, it was simply the economy doing its thing thanks in part to the measured policies of the Federal Reserve Board, but mostly to a business climate that is the envy of the world.

We long have been suspicious about government-imposed mandates to balance the budget, especially when spread out over several years. Budgets are dynamic instruments; their surpluses and deficits cannot be anticipated years in advance. Just as tax revenues are now going through the roof, a national recession could quickly create unexpected financial burdens.

That’s not to suggest, of course, that we spend now and worry later. The current crop of legislators and to some extent, even President Clinton recognize that Americans won’t tolerate big, wasteful government. If we can cut spending, so can Washington.

But setting in stone a budget mechanism for the next five years is a foolhardy and potentially dangerous exercise. At least for now, the economy’s performance is causing some reassessment of the long-discussed plan to balance the budget and cut taxes by 2001.

We can only hope that growth reaches the point where all such considerations are permanently shelved.