Here's a proposition about which most if not all of us surely would agree: These should be good times for the United States of America. The Cold War is over and -- impolitic though it may be to say so -- it looks for all the world as if we won. The economy has been on a binge for nearly a decade, with low inflation and high employment. Environmental problems that only recently seemed intractable now are beginning to yield as clean-air legislation and voluntary recycling take hold.

Yes, there's a lot left to be done and only Dr. Pangloss would say that we're doing all of it. The budget deficit, the homeless, AIDS, the infrastructure, the inner cities, drugs, industrial productivity: The list of social and economic woes is long, make no mistake about it. Yet if in 1980 -- remember the great American "malaise"? -- someone had told us that a decade later things would look as promising as they do now, wouldn't most of us have signed up for a celebration?

So what I want to know is: If these are such happy times for so many Americans, why is it that so many of us seem to hate each other so much? Has anyone else out there noticed it -- the nastiness, the meanness and vituperation that suddenly and inexplicably have become the order of the day? Our president may have been elected on a "kinder, gentler" platform, but we seem to have opted for the darker side of that campaign, the one that wrapped itself in the flag and then gave us Willie Horton. We've become bitter and suspicious toward each other, quick to take offense and just as quick to give it.

The signs are everywhere, from the most trivial to the most blatant. Go to Memorial Stadium in Baltimore and you'll be shocked at the venom with which "fans" now boo Cal Ripken Jr., one of the few genuinely admirable figures in American sport, for the capital crime of a prolonged batting slump. Make a move on the road that some other driver doesn't like and watch out; twice in recent weeks I've been screamed at by urban cowboys in pickup trucks, not to mention given every obscene gesture in the book, because I failed to drive according to their own rules, whatever those might be.

Speaking of obscene gestures: The hottest comedian around is something called Andrew Dice Clay, whose stock in trade is "humor" directed at blacks, women, homosexuals and the members of any other identifiable group he scorns or dislikes. The squabbling over "obscenity" in works of "art" has so divided those on both sides of the issue that they have lost all capacity to speak civilly about each other; instead they hurl slurs and innuendo as enthusiastically as rice is tossed at a wedding.

Speaking of slurs and innuendo: Have you listened to the abortion "debate" lately? That's no debate, officer, that's a shooting match. A question of the most painfully complex moral and ethical nature has been reduced by those on both sides -- but with a special nod to the "pro-life" side -- to an exercise in character assassination. If this is the way serious issues are debated in America today, well, God save the Republic.

And while She's at it: God save the flag. That poor old piece of cloth is in danger of being torn to shreds by all the scoundrels -- chief among them of course the Great Equivocator in the White House -- who've seized the latest Supreme Court decision on flag-burning as an excuse to flaunt their patriotism. So what if their theatrics oversimplify the issue and encourage divisiveness in the body politic? Isn't divisiveness the order of the day?

You bet it is. If you try, however politely, to raise a question that touches on what any racial, ethnic or special-interest group regards as its own preserve, you're best advised to get out your health insurance card; you're going to need it. Question the innocence of Marion Barry or the desirability of an "Afro-centric" school curriculum, and in some African American eyes you're a "racist"; wonder aloud about the wisdom of promiscuous homosexual activity in the age of AIDS, and many homosexuals dismiss you as "homophobic"; express a reservation about the more radical brands of feminism, and you're blown out of the water as a "sexist."

If you're a young black man or woman, try enrolling in a predominantly white college or university; the frats and sororities aren't interested, the professors don't call on you in class, the college newspaper publishes racial jokes and cartoons. So you join the Black Student Alliance and stick with your own kind -- just like the members of the Gay and Lesbian Alliance and the Feminist Alliance and the White Men's Alliance and every other alliance within which two or more similarly aggrieved have taken shelter. Then you get to spend four years of college hating the members of all the other groups, just the way they hate you.

Kinda makes you proud to be an American, doesn't it? All you need to do is show your face on the street and in a minute or two someone will come along who doesn't like the look of it or the color of it or the haircut of it, and who doesn't mind telling you so -- especially if he or she has the safety of numbers. Remember that notorious photograph of white mothers screaming and spitting at a little black girl as she desegregated a school in New Orleans? That was ancient history, right? Well, take your camera right along to Bensonhurst, here in June of 1990, and see what kind of picture you come away with.

The question is: What's going on here? Why has a country that seemed for most of the postwar era to be heading, however slowly and hesitantly, toward that "more perfect Union" envisioned two centuries ago, suddenly plunged itself into a rash of acrimonious disunion? Why has a quarter-century of genuine racial progress left us in what is most charitably described as a state of racial disquiet? Why has calumny rather than conciliation become our preferred method of political discourse? Why is there so much meanness in the air?

Your guess is good as mine. Probably better. But there's something to be said, I think, for the argument that we're simply bored. For all the disputation and dislocation of the postwar years, middle-class America has had it pretty easy for more than four decades. Add to this an international situation that's gone overnight from apocalyptic confrontation to tempests in distant teapots, and what it comes down to is that we have time on our hands.

Human nature, in such circumstances, is just like Mother Nature: It abhors a vacuum. So we've figured out a nice way to fill it. Instead of drawing together in common cause against fierce enemies or terrible problems, we've split asunder in petty contention over minor disagreements -- minor at least by contrast with the overarching issues of the postwar years. We've gotten complacent and smug; we've also been encouraged, in the prevailing atmosphere of recent years, to vote the old "I'm for Me First" ticket, introduced as a joke by Roger Price in the 1950s but elevated to received wisdom by Ronald Reagan and his apparatchiks.

So what it says here is: If these are the good times, Lord protect us against the bad.