Personal responsibility is also one [reason to vote conservative]. When I think of a gay person who lives responsibly, saves his or her money, goes to church, contributes to charity and settles down in a stable relationship, I think: conservative. When such a couple wants to get married, I think: conservative. When such a person decides to serve his country in the military, I think: conservative.Sorry, Andrew. These are not "conservative" virtues or characteristics, they are characteristics of most ordinary, civilized people. The implication that liberals--gay or straight--are irresponsible, profligate, godless, selfish, bed-hopping cowards is insulting and base.
Although I'm an atheist and not a churchgoer (but many liberals do go to church), this "liberal" is a responsible person, is employed, has a savings account and (soon) investments, is married, and contributes to charity. I never served in the military (and neither has Sullivan, to the best of my knowledge), but I pay my taxes and I recognize at least in theory that we must have a military to protect our nation. (The military has not, however, actually been used for such a purpose since 1944, or perhaps 1812, or perhaps even 1776. But that's another story.)
None of this has anything at all to do with "conservatism", "liberalism" or anything in between.
I'm a liberal because, unlike conservatives, I believe that I have a positive obligation to actively promote the happiness of my fellow citizens and my fellow human beings, and this responsibility is by virtue of my citizenship, not just my particular preferences.
I'm a liberal because, unlike conservatives, I believe that as much as I admire what's good about my country, we have no sort of obligation whatsoever to promote our values at gunpoint; indeed we have an obligation to the contrary.
I'm a liberal because, unlike conservatives, I do not become paranoid and delusional and see existential threats in a few criminal acts, however horrific, perpetrated by cave-dwelling religious fanatics.
I'm a liberal because, unlike conservatives, I figured out that "compassionate conservatism" is an absurd oxymoron; and I figured it out in 1999.
I'm a liberal because, unlike conservatives, I recognize and reject the conservative dog-whistle of "personal responsibility" as "I've got mine, Jack."
I'm a liberal because, unlike conservatives, I do not ask for whom the bell tolls: It tolls for me. Every time.
Update: (25 Feb 07) This little rant is getting a fair amount of press. I think it's worthwhile to make my position crystal clear in simple declarative sentences.
I don't object to Sullivan drawing a distinction between conservatism and liberalism on moral grounds; I agree that the distinction is indeed moral. I don't object to Sullivan (or anyone else) presenting the moral distinction in a way favorable to his own position; this is the function of any advocate, including myself. I find Sullivan's appropriation of ordinary civic virtues to the position of conservatism to be objectionable and intolerably sanctimonious.
All of the distinctions I myself draw between liberalism and conservatism relate to actual differences between how I see liberalism and how I see the stated positions of many conservatives. I may be mistaken, but some of the comments seem to indicate that I have indeed hit points of real controversy.
 Technically "anarcho-humanist"; I'm using "liberal" here to mean just "not a conservative".