Democrats' rough 'n tumble realignment. Black-Jewish confrontation may be evidence of a long-term shift in party makeup

A political insider, close to both major parties, looked at the latest wild week of Democratic Party politics and concluded: ''When the smoke clears, we're going to see a realigned Democratic Party, with a new constituency, and some of the old (constituency) being driven off.''

It was a week that had Democratic Party leaders pulling their hair.

Louis Farrakhan, the Black Muslim leader, started things by blasting Jews and Israel with the meanest kind of language. Walter Mondale then ripped into the Rev. Jesse Jackson, whom Mr. Farrakhan supports, for not criticizing Farrakhan. Mr. Jackson responded by tearing into Farrakhan. Mondale quickly praised Jackson. And, finally, Jackson had kind words for Fidel Castro.

Confusing? Yes, but for Democratic Party leaders, also very worrisome. Black Muslim leader Farrakhan is not the person they want setting the tone for the party on the eve of their convention in San Francisco. His flaming rhetoric against Judaism and against Israel threatens to dig a gulf between blacks and Jews - both critical to Democratic success in the fall. Although the Jackson campaign issued a statement disavowing Farrakhan's comments (Farrakhan reportedly called Judaism a ''gutter religion'' and Israel an ''outlaw''), some analysts say the damage has been done.

Jackson himself makes many supporters of Israel uncomfortable with his calls for a more evenhanded approach in the Mideast and direct dealing with the Palestine Liberation Organization.

David Chagall, publisher of Inside Campaigning, is one of those who feel a long-term shift is taking place within the Democratic Party.

''I think it's a historic change,'' Mr. Chagall suggests. In the 1984 election, he says, it won't be surprising if more than half the nation's Jewish voters support Ronald Reagan.

One reason: Walter Mondale, eager to hold his black support, will probably ''be seen to cut a deal with Jesse Jackson.'' Mr. Mondale must court blacks, who now make up about 10 percent of the total vote, and about 18 percent of the traditional Democratic vote nationwide.

Democratic insiders say the black-Jewish split is their greatest worry going into this month's national convention in San Francisco.

No decision has been made on whether Jackson should be allowed to address the delegates. Nor is it clear whether Jackson will have any other major role at the convention. If Jackson is given no official place, it could anger and alienate many blacks, for whom he has become a champion. On the other hand, a prominent role for Jackson could scare away Jewish support.

A high-ranking official in the campaign of Sen. Gary Hart says the black-Jewish split is only hastening the exit of some Jews from the Democratic Party. The trend, he says, was already under way before Jackson became a candidate.

A large number of Jewish voters, the official says, are pleasantly pleased with the economy under President Reagan.

Further, many Jewish voters like Reagan's ''macho'' foreign policy, which they think is good both for the United States and Israel.

Predictions that a majority of Jewish voters might go to Reagan this year don't surprise the Hart official. In fact, he says, such predictions only confirm some of the trends that the Hart campaign has been detecting.

Jackson was out of the country when Farrakhan unleashed his latest attack on Israel and its supporters. After a brief delay, Jackson campaign manager Arnold Pinkney read a statement from the candidate that denounced Farrakhan's comments as ''reprehensible and morally indefensible.''

The Jackson statement noted: ''I will not permit Minister Farrakhan's words, wittingly or unwittingly, to divide the Democratic Party. Neither anti-Semitism nor antiblack statements have any place in our party.''

Republicans quickly tried to take advantage of the Democratic dilemma. GOP chairman Frank J. Fahrenkopf Jr. said the Black Muslim minister's words were ''reminiscent of the language used in Nazi Germany. It is hardly the sort of comment one would expect from an adviser to a Democrat candidate for president of the United States.''

The US Senate voted 95 to 0 to condemn Farrakhan for ''hateful, bigoted expressions of anti-Jewish and racist sentiments.''

Farrakhan, interviewed by Cable Network News, said of the Senate vote: ''And there is not one black senator, is there?''

Farrakhan said he was not bothered by Jackson's repudiation of his comments. He said: ''If it will help him go to the (Democratic) convention and represent the 85 percent of the blacks who voted for him . . . then the rebuke or the repudiation is well worth it.''

Mondale, who found himself relegated to the inside pages in recent days by Jackson's Cuba trip and Farrakhan's comments, ended the week praising Jackson.

''I commend Rev. Jackson for . . . making it clear that Mr. Farrakhan has no part in his campaign,'' Mondale said. ''The only way to advance the cause of justice in America is to condemn bigotry and prejudice wherever it appears.''