Last week's Washington tempest blew in when Sen. Rick Santorum, R-Pa., said that if the Supreme Court in a pending case rules that homosexual practice is constitutionally protected, "then you have the right to bigamy, you have the right to polygamy, you have the right to incest, you have the right to adultery. You have the right to anything."

Gay advocacy groups quickly made political hay. The Human Rights Campaign expressed outrage that Santorum "compared homosexuality with bigamy, polygamy, incest and adultery" in his "deeply hurtful" remarks. The Center for Lesbian and Gay Civil Rights similarly complained that "his remarks show nothing but contempt for lesbian and gay people."

Whoa! Who's showing contempt here? Logical gay groups should applaud Santorum's recognition that a Supreme Court gay breakthrough will also bring liberation for others with non-monogamous sexual interests. Since when do homosexuals look down on others who follow their own bliss? But maybe this is good news: Our headline could read, "Gays join conservative Christians in criticizing bigamy, polygamy, incest and adultery."

The Pennsylvania Gay and Lesbian Alliance unctuously proclaimed, "Discrimination against any group of citizens based on who they are is simply wrong" -- yet the gay lobbies were implicitly discriminating against those involved in consensual incest. "Extremism in the defense of vice is no vice," they should say, and then proceed to the postmodern claim that it's all a matter of opinion whether a particular act is vicious or virtuous.

But let's move to the politics, since this is all about trying to drive a wedge within the GOP. "We're urging the Republican leadership to condemn the remarks," said David Smith, a spokesman for the Human Rights Campaign. "They're the same types of remarks that sparked outrage toward Sen. Lott."

No, they're not. Trent Lott resigned his Senate leadership post in December after making remarks widely seen as supporting racial discrimination. Lott's words ran counter to the Bible, which is color-blind. Santorum's words reflect the Bible, which says that homosexual practice, like adultery or incest, is wrong. President Bush, who looks to biblical teaching for guidance on important issues, rightly criticized Lott, but he should support Santorum continuing as conference chairman, the third-highest seat in the GOP Senate leadership.

Good politics, good theology, and good constitutional law go together here. The Republican Party should be open to Bible believers, people of other religions and atheists, but if it wants to retain the support of Christians and Orthodox Jews, it should not chastise those who defend biblical truth. Besides, even though the state of Texas may have been unwise under current social conditions to prosecute a case concerning homosexuality, the Supreme Court should not establish a new, loose constructionist constitutional right.

Some Republicans who covet gay lobby campaign contributions will pressure the president to signal a Santorum sack. Because he spoke out in the Trent Lott controversy, he should not sit this one out; Santorum foes will see silence as consent. This is a crucial political fork in the road, and the George W. Bush -- who was tough enough to stand up to supporters of Saddam -- should refuse to be pushed around by supporters of sodomy.

Instead of being defensive, Republicans who are both wise and shrewd will go on offense. They should ask gay interest groups and Democrats to respond to Santorum's challenge: Make a constitutional argument that will differentiate the right to consensual gay sex from a right to bigamy, polygamy, incest, or adultery. Legislatures, of course, have long differentiated among certain acts, but what happens if the Supreme Court tells them to cease and desist?

Republicans (and others) who want to become wiser on such issues should read "What We Can't Not Know," a new book by my University of Texas colleague J. Budziszewski. The book is not a Bud Light, but non-professors can readily follow its discussion of "natural law," the "developmental spec sheet" that God has given us. As Santorum knows, once we move off that spec sheet, anarchy reigns.