Why did Sen. Larry Craig resign? Was it that he was exposed as a homosexual? That he is also a Republican? That he lied? That he committed a misdemeanor? That he is a hypocrite? Or that Republicans had to offer him in sacrifice lest they too — horrors — be accused of party-wide hypocrisy?

Obviously, he resigned under pressure from the left — which ought to be defending him — and his GOP colleagues.

The larger question, then, is why both the left and right came down so hard on Craig. MSNBC’s Chris Matthews inveighed against Craig because Republicans have railed against “San Francisco Democrats” and “hypocrisy does loom here.”

Matthews’ “Hardball” guest, Salon’s Joan Walsh, agreed. “Hypocrisy absolutely looms, Chris. …The Republican Party has made itself the party of the bedroom police. They’ve gone after gays, they’ve snickered about San Francisco Democrats, and they went after Bill Clinton in a sexual kind of witch hunt, and so they’ve left themselves really open to double standards.”

Not so fast, Chris and Joan. While many “values voters” admittedly disapprove of homosexual behavior, they are not anti-gay in the sense liberals are suggesting.

I don’t know of any Republicans or conservatives who engage in or advocate bedroom policing — a smear that is too-often repeated and accepted unquestioningly.

It’s simply not true that opposition to abortion, the elevation of “sexual preference” to the status of race under our civil-rights laws, the societal sanctioning of homosexual marriage, or allowing homosexuals to serve as Boy Scout troop leaders constitutes bedroom policing.

Even the charge Craig is suspected of involved public, not private, activity. No one is advocating that sodomy laws be resurrected and enforced or that government video cams be installed in our homes.

And, truth be told, conservative denunciation of “San Francisco Democrats” is due to their extreme liberalism and in-your-face demand that society normalize, even celebrate, homosexual behavior, not to some vendetta or crusade against homosexuals. In addition, the charge that Republicans conducted a sexual witch hunt against Bill Clinton does not become more credible with endless repetition. He was pursued for perjury and obstruction of justice.

So how can Republicans fairly be accused of hypocrisy here? They cashiered Craig immediately, which is light years faster than Dems police their own, i.e., rare to never. Surely liberals can’t say with straight faces that either Craig’s suspected behavior or the Republicans’ swift response to it contribute to the “culture of corruption.”

But isn’t Craig a hypocrite? I’m not so sure. In the first place, Craig has denied he’s homosexual. Aren’t Democrats champions of the presumption of innocence? I realize this presumption generally only applies to criminal accusations, but liberals are always demanding that we also apply it to our discourse so that we can’t even opine about one’s culpability in a matter without violating the sacred presumption of innocence.

Remember how many of them objected to pundits’ opinions — pre-verdict — that O.J. was guilty? So unless Democrats want to concede their own hypocrisy, they must assume Craig is not a homosexual since he denied it.

Besides, isn’t it highly presumptuous to conclude that it’s impossible for a homosexual to disapprove of homosexual marriage or other special rights for homosexuals?

Democrats might object that the presumption of innocence doesn’t apply to Craig because he already pled guilty. But that’s not a satisfactory answer since his plea didn’t necessarily imply an admission that he solicited or engaged in homosexual activity.

But wait. Joan Walsh made it clear the presumption doesn’t apply to Republicans. When Matthews, to his credit, challenged her for condemning Craig over the “longstanding rumors” of his homosexuality, she protested that the Idaho newspapers have documented Craig’s pattern of behavior — as if newspaper accounts override the presumption and as if such patterns (see: Bill Clinton) ordinarily matter to liberals like Walsh.

But more troubling than any of the above are liberals’ efforts to make GOP hypocrisy an “impeachable” offense. Even worse is their exploitation of the Craig episode to undermine society’s preservation of moral standards under the staggeringly ludicrous reasoning that sinners (read: everyone) are disqualified from condemning sin. This is nothing short of a prescription for wholesale anarchy and the disintegration of our moral fabric: Judges couldn’t be judges, legislators couldn’t legislate, prosecutors couldn’t prosecute, pastors, priests, and rabbis couldn’t serve. Worst of all: Columnists couldn’t sermonize.

As for me, I won’t lose any sleep over Craig’s departure because I happen to believe his guilty plea points to his culpability on the underlying charge to which he did not plead — and I’m not bound by liberals’ selective demands that we expand the presumption of innocence to preclude the airing of our opinions of guilt.