We must be the most self-conscious nation on earth. The echoes of our great yelling shrieking laughing, weeping welcome to our hostages had scarcely faded when we reconstituted ourselves, collectively, as a kind of Mount Rushmore-size national psychiatrist and intoned in the gravest of voices: "Now what did we mean by that?"

The answers, the critiques are tumbling forth. They are a model of mutual contradiction and adamantly opposed views. I agree with all of them. I think the nation was in the mood for a good holler, and I think I heard in the roar that went up all the various feelings that various analysts have said were there -- embarrassment, pleasure, relief, rage, impatience, a desire to drown out disgrace, a desire to spit in the ayatollah's eye . . . and so forth. But above all, I think what was important about the response was its very magnitude and volume, the sheer un self-consciousness of it -- at least until we state troopers of the analyzing press caught up with the proceedings and asked them to pull over to the side of the road.

Among the perpetrators of the festivity, of course, was the new president of the United States. Even though he and his national-security advisers are reported to believe that the year of the hostage was a far from creditable episode in the nation's life, especially with respect to its government's conduct, he was right up there leading the exultation and the noise. Reagan prayed and blessed and praised and thanked. He also boasted about our strength and resolve and told prospective tormentors and tweakers to look out.

What interested me most in the Washington reaction to all this was the ambivalence, even turmoil, it seemed to stir in the breasts of the anti-Reagan dispossessed and other assorted sophisticates around town. There was a peculiar alternating current they emitted. One minute they would tell you, in an air of wonder and confession, that they actually felt good . . . happy . . . teary . . . patriotic. The next, they were worrying about jingosim, cold warriorism, demagoguery and what they seemed to regard as a wanton and contemptible effort to rehabilitate apple pie in the age of spinach quiche.

Right here, you get as good a glimpse as you are likely to of what is really changing in this city and in our politics generally; you get an idea of what ronald reagan seems to have brought to Washington, which is also what brought him here. I don't for a minute buy the idea that American values are changing (reverting, as some say) or even that vogues in American values are changing ("All of a sudden it's fashionable to feel patriotic again!" a TV reporter cried into the microphone last Tuesday in mid-parade). What is new is precisely this unself-conscious, blunt willingness to acknowledge the universal, the eternal and self-evident.

These values and emotions can seem "new" or newly respectable or surprising or exotic only because it has been considered somewhat unintelligent and vaguely embarrassing by some to concede their existence for so long. But I am certain they were throbbing awy there, unspoken and unadmitted, among even the most dissenting, counter-everything of us all these years. And if there is a complaint from the crowd I run with (and there is), it is that the new president is winning a claim for merely uttering truisms. I say that is the fault of those who disregarded or disavowed these truisms for so long that Reagan can now get credit for retrieving them from the political junkyard and reinstating them in his speeches.

This willingness to enuciate uncomplicated, conspicuous truths or to acknowledge fairly direct cause-and-effect relationships that have a certain rough-schoolyard element of justice to them has -- naturally -- its downside. The fabled mink-and-money show in inauguration week provides an example of sorts. Styles have changed in Washington. But before you get to the meaning of this you have to clear away a certain amount of political and rhetorical underbrush.

You would have thought from all the shocked, instant anthropology made available through the media that the upper reaches of politics had never seen fancy clothes and cars and jewels before. Some saw this as a restoration of "class" and elegance, others as a restoration of I-got-mine-you-get-yours social Darwinism. The unhelpful truth is that the reigning, liberalish celebrity group that has been jolted, if not actually displaced, by the new crowd can probably match it mink for mink and karat for karat. The liberals' conceit that their furs come lined with social consciences will not impress the multitudes.

But the point is that the Reagan people seem, once again, rather less apologetic and ambivalent and self-conscious about their wealth -- just as they are about other values that are not contingent on money. Maybe this does bespeak a certain hardness and social irresponsibility. If it does, God knows, we'll find out soon enough. But there is something remarkable, even refreshing in the candor -- since their husbands had earned the money and were all self-made, one of the Reagan in-group women said, why shouldn't they spend it as they pleased ? This widely reported remark had a definite resonance for me, and after much meditation I located it in memory. It was Ronald Reagan's clincher in the New Hampshire debate: "I am paying for this microphone, Mr. Breen. . . . I should have some right. . . ."

A certain stark truth and justice there. A demonstrable cause-and-effect connection. Almost too obvious to need saying -- like so much else: people who do us harm shouldn't think that we don't notice, people who help arrange trouble for us will not get special favors in return. Ronald Reagan & Co. have a gift for validating our most fundamental and uncomplicated appreciations of reality -- political and emotional. It is why he was the right man to have up there on the reviewing stand when the hostages came marching home. But that, of course, was last week. The next question is whether this administration can move on from the statement of basic truths to the creation of working policy.