Once conservatives battled rigid quotas. Now they attack all affirmative action programs meant to encourage greater inclusion of blacks in American institutions. Once conservatives promoted programs that required work in exchange for welfare benefits. Now they want to cut families off benefits entirely.

Black conservative intellectuals are faced with rebutting arguments like those made by Charles Murray in ''The Bell Curve,'' which suggested that blacks might be genetically inferior, or countering arguments made by Dinesh D'Souza in ''The End of Racism,'' which held that blacks are culturally inferior.

A few weeks ago when I suggested to a gathering of conservatives that their seeming hostility to every social program smacked of indifference to the poor, I was told that a surgeon could not properly be said to have no concern for a terminally ill patient simply because he had moved on to the next case. The analogy alone speaks volumes.

Just last month, I heard a top aide to a Midwestern Republican senator tell cultural conservatives that, in the name of restoring ''traditional American values,'' his boss sought to ''build a bridge to the 19th century.'' (Now that's turning back the clock!)

I have tried to argue with my fellow conservatives about the nuances, complexities and moral ambiguities of issues like welfare, affirmative action and drug control policy. But I have succeeded only in arousing the suspicion that I am not a ''true believer.''

Indeed, my views on affirmative action have evolved, and that is seen as a betrayal. At a conference in Washington this fall of conservative intellectuals, I suggested that a modest degree of affirmative action in higher education could be justified. That prompted an angry response from Norman Podhoretz, the conservative writer and editor, who called me ''disingenuous'' and added, ''I much prefer the old Glenn Loury to the new one.'' The discussion limped along from there.

My dilemma is not unique. Consider the case of Robert Woodson Sr., the president of the National Center for Neighborhood Enterprise. For 20 years, Mr. Woodson has been criticizing the agenda of black liberals, but he has also been helping grass-roots organizations expand economic opportunities in their low-income communities.