<Please don't tell me that liberals don't tend to lean toward moral relativism.

No, that would contradict someone else's opinion you've already adopted as your own, wouldn't it?

Something I noticed in what you said seems to be contradictory. In one statement, you said that you're bothered by Santorum's public policy against homosexuality:

"My problem is his apparent perspective about what public policy should say about such behavior."

Yet, on the other hand, you say that you don't have any problem with public policy restricting the rights of homosexuals:

"I am perfectly comfortable with laws which confine the legal institution of marriage to a single individual of the opposite sex."

I understand that there is a difference between homosexual sex, and homosexual marriage, but I think that you would find that the right to be recognized as a legally married couple is of much bigger imporance to homosexuals than the right to do what they want in their own bedroom....an aspect which, admittedly, can't realistically be policed anyway.

The case before the Supreme Court is all about whether a state not only can, but insists that it should, police such activity, no matter how arbitrary or capricous the enforcement may seem. A suprisingly large number of states have similar statues on their books, too, some of which declare certain practices illegal between consenting hetero adults.

Nice try, bending the issue around to what you perceive to be a 'gay agenda' issue - same-sex marriage. What really bothers you, so I infer, is that Don's personal opinion doesn't jibe with your pre-concieved notions that "all liberals support issue X because they support Z." In other words, Don doesn't fit the pigeonhole you've labeled "Liberal."

Now let's return briefly to Santorum - he was Trolling, pure and simple. I don't doubt for a moment that he knows the differences in legal nicety between sexual behavior and marriage - he combined the issues to bait the Right (his side, in case anyone was missing that) into reflexive response.

This is one of those issues where the dovetail of Liberal and Libertarian beliefs fits very nicely: the Government does not belong in the consensual adult bedroom. Rape (including the spousal variety) or other violence are the non-consensual exceptions; the non-adult ones need not be delineated.