The Democrats were thrashing around last week, trying to rearrange themselves. The governors were in town, alternately emitting stoic professions of good citizenship and wounded-animal cries at the news of Ronald Reagan's proposed budget cuts. From Capitol Hill, the unions and the lobbies came the first truly ominious rumblings of dissatisfaction with some of the Reagan economic and foreign-policy initiatives. And you could tell from even a casual reading of their work that the media-natives were getting restless, too.

What we were witnessing was the early struggle, confused and uncertain, of a political opposition to create itself. What was interesting about it was the tension between those prepared merely to pursue ancient and reflexive grievances against the Republican right and those more wary, who believe the terrain is new and therefore more treacherous for those planning an assault. Not that these different sentiments are found only in different groups of critics. More typically they are found at war within the same individual. I passed some time last week with Democratic officials who would veer suddenly from classic denunciations of a socially heartless, Russia-obsessed Reagan to apprehensive assertions that he might, God forbid, be on to something and that the only thing for their kind to do was sit back and wait and seize whatever opportunity might come by to make him look horrid.

Traditionally, of course, it is just about now that the first signs of discontent with a newly installed administration become noticeable. Yet I think that this time around there are important differences and that these may cause the opposition to Reagan to develop differently.

For one thing, Reagan's victory fulfilled the desires of a lot of people on the right who have been disappointed so often until now that they have made a way of life of opposition to prevailing political authority. Richard Nixon's dalliance with welfare reform, his opening to China and the rest, and Gerald Ford's various concessions to the establishment agenda only confirmed their suspicions and their apparently permanent status as betraved outraged observers. These were (are) people who had nothing to show for their political involvement but the luxury of being able to holler when everyone else was having to justify and explain why things didn't work, and the blissful security of knowing they would never be embarassed by having their ideas put to the test.

Well, that's changed now, and one of the imponderables in the formation of our revised political life under Reagan is how these folks will take to being the upbeat ones, the optimists, the defenders. Some of them, especially among the farther, crankier reaches of the media, have the aspect, to me, of all the bad boys I ever knew, dressed up for Sunday school. They may be temporarily chastened by the way they have been made to look and been commanded to behave for the occasion, but those cowlicks don't stay plastered down very long, and generally, by 11 o'clock, all hell has broken loose.

Back in the days of the Kennedy administration, it used to be noted that House Republican leader Charley Halleck of Indiana had inherited only one mode of behavior from a near lifetime in the opposition and one controlling expression: "I gotcha licked." Similarly, there is a question whether these latter-day lifetime oppositionists, whose misfortunes have been reversed by Reagan, will be able to resist the urge to start fighting him in time.

Among the odder features of our contemporary politics has been the fact that at least through the past four presidencies, the president himself has also sought to be identified with the anti-federal government forces at large in the land. This too has rather confused the delineation of in- and out-group politics, as those in charge of the great federal engine and its often ghastly works run against it for reelection as if they'd had nothing to do with the source of all the complaint. It is possible, therefore, that given the Reagan constituency's traditional opposition to government and the temptation the president will face to keep campaigning against it, even as he becomes its putative embodiment and boss, the lines between incumbent and challenger will stay pretty murky.

This is, I suppose, all the more probable in view of the Democrats' frequently professed new need to "rethink" their ideas and ambitions. What I sensed among those I talked to last week and in the published statements of others was a genuine tension between trying to figure out the landscape of our present politics on the one hand and, on the other, merely pursuing every emotionally comfortable, conventional, if now irrelevant dispute they ever had with the Republican right. Is everything really just another Vietnam? Are all the Reagan proposals merely rich man's revenge on the poor? Everything seems to remind some of these folks of earlier, perhaps more clear-cut battles. It strikes me as the best possible, absolutely guaranteed way to lose the next political war.

Reagan himself and many of those around him in some unfortunate respects encourage this. I don't think El Salvador is Southeast Asia revisited. But it is also not Eastern Europe in 1947. The overstated, too stark, even somewhat quaint and nostalgic, declarations about, say, the Russians' or Cubans' involvement in other parts of the world dissipate what good might be done by having the courage and clarity to talk frankly about some of these things again, reducing them to caricature and, inevitably, inviting a comparably overstated response from the Democrats.

We can have, in other words, the same old fights we've been having since anyone can remember, or it is just barely possible that a political opposition and a dialogue will develop to fit the reality of our circumstances. Will it be strawmen fighting strawmen? Echoes drowning out other echoes from a past we are -- or thought we were -- mercifully done with? Or will those who are cranking up to function as serious critics of the prevailing powers and the people themselves who finally wield that power just for once engage in a way that's worth watching and even joining?