I admit to being among those who thought President Reagan was properly tough when he refused to countenance the illegal strike of the Professional Air Traffic Controllers Organization.

It was time, I thought, for someone in authority to say that no-strike agreements, such as the one PATCO had signed, were more than words on paper. Time and again I had seen postal workers, teachers, firefighters, police officers and other public employees disregard their no-strike pledges when it suited their fancy. Seldom were they punished, beyond being assessed fines.

More often than not, final agreements included amnesty for the illegal strikers. Even judges whose back-to- work orders were openly defied routinely agreed to lift contempt charges once the illegal strikes were settled.

Reagan, in declaring on Aug. 7 that PATCO's illegal five-day strike was over and that the controllers would be replaced, served notice of a new day in labor relations. I thought it a good move--legally, politically and morally.

But that was five months ago, and it's time for the president to take a new look. He ought to pay attention to those who are urging him to find a way to put the workers back to work.

In doing so, he would be continuing a long American tradition of being uncompromising in war and generous in victory. If America could restore its relations with Germany and Japan, elevating those vanquished countries to the status of allies and helping to lift their economies to unprecedented heights, surely it can muster enough compassion to help the defeated air traffic controllers to go back to supporting their families.

So far, President Reagan has done just the opposite. He not only fired the illegal strikers, but he has moved also to block their employment by other government agencies, even blocking their applications for unemployment benefits. He said last week that he was considering rescinding the order that barred the fired controllers from all federal employment. That's a tiny step in the right direction. He ought to be looking for a way to put them back in the control towers--at least those who are now conceding that they made a horrible mistake last August.

"You've got to wonder, what more do they want from us?" a local union leader said in a recent interview.

It's a fair question. It is hard to see how it serves the nation's interest, or the president's, to continue on the current vindictive course.

As a former union president, Reagan ought to understand that the necessity for solidarity sometimes can lead workers to do foolish things, especially when they are certain that they are right on the basic issues. The air traffic controllers clearly thought they were right to demand some relief from the stress of their jobs: the tough hours, the deteriorating equipment, the pressures that led to an uncommon number of medical retirements. Indeed, candidate Reagan agreed with them and pledged, as president, to do something to help. Obviously they miscalculated in assuming that his pledge of support meant that they would not be punished for their illegal strike.

There is no doubt in my mind that Reagan was right to do what he did in August. The question is, what should he do in December? What he should do is to put these highly trained specialists back to work.

Virtually every fact urges that conclusion. True there has been no air disaster traceable to the firing of PATCO members; the skies seem reasonably safe. But one of the reasons this is so is that air traffic is diminished by some 25 percent.

The airlines have lost money, and machinists, flight attendants and workers in air-related industries have lost jobs as a result of the curtailment.

But the greatest tragedy involves the lives of the fired controllers themselves. PATCO is a union, and it is arguable that it deserved to be tamed. But the air traffic controllers are men and women with families to support, with mortgages to pay, with bills that cannot be met. Isn't it time to show some compassion for them? Their union has been busted. What's the point of busting their lives as well?

Reagan's point is that they knew they were breaking the law and that they had been warned, in the clearest terms, of the consequences. But even repentant criminals deserve a second chance.

Clearly there would be some difficulties. A number of new controllers have been hired, and there won't be enough jobs for both them and the 13,000 who were fired. But not all the 13,000 would be looking to return to the towers, and some--the defiantly unrepentant-- may not deserve to.

But the details wouldn't be that hard to work out if the president could bring himself to utter the basic, magnanimous words: Come back. All is forgiven. We need you.

He could call it a Christmas gift from the nation