THERE HAS BEEN a transformation of American anti-Semitism in recent times. The crude anti- Jewish bigotry once so commonplace in this country is today gauche; Jews are no longer the butt of vaudeville jokes, put-down stereotypes on stage and screen, or grotesque characterizations in cartoons and comic strips.

No quotas bar Jewish students from the ivyest of schools. Jews reside in the most exclusive residential neighborhoods; hotels and resorts are wide open; "No dogs or Jews" signs are childhood memories. And while some social anti-Semitism lingers, Jews are ensconsed in the executive suites of important industries. The Ku Klux Klan, so menacing in the early years of this century, is a tattered remnant of itself, no more than an irritating nuisance, despite its ability to attract the attention of the media.

The most disturbing recent evidence of overt anti-Semitism -- the sudden rise in reported incidents of anti-Jewish vandalism from 1979 through 1981 -- seems to have peaked. Even at its height -- 974 reported incidents in 1981 in a population of 240 million, according to figures kept by B'nai B'rith's Anti- Defamation League -- the number was a cause for concern rather than apprehension.

To cap it all, poll after survey indicates that Jews are one of America's most highly regarded groups.

So, if Jews in America are doing so well, what's there to worry about?

The answer would not have been readily visible even a decade ago. Danger to the Jewish people today lurks in the oddest of places, in situations far removed from traditional anti-Semitism.

For instance, no organization more innocent of bigotry could have been conceived than the United Nations. But the U.N. today is a cauldron of crude anti-Semitism. U.N. resolutions equating Zionism with racism are as common as descriptions of Jews as kikes years ago. The anti-Semitic fallout is no less invidious.

The 1981 AWACs debate provided a textbook illustration of how anti- Semitism can emerge from an a-Semitic issue -- AWACs, like oil, being neither anti- nor philo-Semitic. The reservoir of dormant anti- Jewish feeling tapped by public figures who chastised only Israel and American Jews for their lobbying efforts -- which, it was claimed, were against American interests -- had effect. The AWACs were sold to the Saudis largely because enough well- meaning senators were persuaded that it would be better for the Jews to lose to avoid an anti-Semitic reaction in the nation.

The search for peace in the Middle East is littered with minefields that endanger Jewish interests. Here, again, Jewish concerns are confronted by the Semitically neutral postures of those who believe that if only Israel would yield this or that, the Middle East would become tranquil and the West's highway to its strategic interests and profits in the Persian Gulf would be secure. But at what cost to Israel's security? Israel's security, plainly said, means more to Jews today than their standing in opinion polls.

Fevered language describing Israeli actions in reporting from Lebanon last summer such as "genocide" and "holocaust" illustrate how decent yearnings for "peace," in an alchemy of high dudgeon, historical ignorance and hyperbole stir anti-Semitic imagery.

To many, aware of the Jewish record of opposition to racial and religious discrimination, Jewish opposition to racially preferential treatment seems inconsistent. Nothing, however, could be more consistent with the traditional Jewish position against discrimination and for equal opportunity based upon individual merits. Whatever the euphemism, a quota system is a quota system. The idea that group proportions in the population is a criterion for education and employment is mischievous.

We and the world have grown more complex in our concerns. Indeed, who would ever have thought that Jews would have a Jewish interest in America's military credibility? An America unable to protect itself against the Soviet scourge would be an America unable to protect Israel, let alone Jewish citizens in a Finlandized Western Europe.

In their long history, Jews have experienced virtually every form of government. None have proved without vicissitude, but of them all Jews have flourished best in America. It has always been true that what was good for the Jews and other minorities was good for the American ideal; today we know that what is good for the well-being of our American democracy is good for all its minorities.