In July, Commentary Magazine published an article by Irving Kristol, a leading neo- conservative, telling American Jews it was time they faced reality and voted Republican. The article was a tutorial in which Kristol tried to explain to his co-religionists that they should not fear Jerry Falwell. As a latter-day Moses, Kristol was a magnificent failure. He led but almost no one followed.

Nevertheless, when it came to Falwell, Kristol had something of a point. He was attempting to tell the Jewish community that just because Falwell spoke with a southern accent, was a born-again Christian and espoused conservative causes, he was not the archetypal anti-Semite of lore. Sometimes something that walks like a duck, talks like a duck and acts like a duck is not a duck.

Now, there another non-duck to contend with. They are the 35 conservative members of Congress, almost all Republicans, who wrote to the South African ambassador recently, saying, in essence, that just because they were conservative does not mean that they're racist. The letter was written by Rep. Bob Walker (R-Pa.).

The chances are that in the short run the importance of this letter will go the way of the Kristol article. People, especially liberals, are so accustomed to equating conservatism with racism that they will consider the letter an aberration and forget it. At the very least, though, it means that when it comes to civil and human rights you can no longer count on the new conservatives' being, well, conservative.

But it means something else, and the White House, not to mention the Democratic Party, ought to pay attention. In the letter, the conservatives concede the strategic importance of South Africa but say that's no reason "to condone policies of apartheid." If this says what it appears to, then there is something new under the sun -- conservatives saying that anti-communism is no justification for human rights abuse.

This is a total reversal of traditional conservative dogma. Wherever aging Young Americans for Freedom gathered, it was enough for a country just to be anti-communist. After that, it could kill, torture, maim, repress. It could, in short, be Chile, Argentina, Paraguay, Greece under the colonels, Iran under the shah and South Africa under the Afrikaners -- especially South Africa, since it, like old-time conservatism, cherishes both free enterprise and the white race.

Although the letter's signers go out of their way to praise the administration's handling of South Africa, they are actually quibbling with it, saying that because a black nation run by white racists cannot endure "constructive engagement" is to no one's benefit. In other words, apartheid is not only morally wrong, but shortsighted as well -- and tolerance of it by the administration, even in the cause of anti-communism, is equally shortsighted. Say what you will about Ronald Reagan, he finally got the message. Four years into his presidency, a "moral responsibility to speak out" overcame him and, throwing caution to the wind, he -- brace yourself -- denounced South African racism.

The question now is whether the Democrats will be as attentive to the new conservative posture as the White House has been. Up to now, to be black and to be a Democrat has been a redundancy, but that is clearly something the new conservatives are trying to change. Rep. Jack Kemp (R-N.Y.) spoke before the Urban League, and like-minded conservatives (but not Kemp) signed the letter to the South Africa ambassador.

If Jews needed something more than the word of Irving Kristol to vote for Ronald Reagan, then clearly blacks will need something more than a mere letter to make them vote Republican. After all, black indifference and hostility to the GOP is no mere accident. They have been earned. But a new generation of conservatives is reaching out to a new generation of blacks. These conservatives sent a letter to the South Africa ambassador, but it was really not a letter, and it was meant for someone else. It was addressed to American blacks, and it was an invitation to a party -- the Republican one.