It’s not hard to see why pornography has always the power to unite the left and the right: American culture has never been particularly comfortable with sex. Despite some major strides that movements for sex workers' rights have made over the past few years (including, thanks to her willingness to stand up to her ex-lover and the current president, the pop hero status of performer Stormy Daniels), pornography still remains a deeply stigmatized industry, and one presumed to be populated by the vulgar, immoral and dumb, perhaps not entitled to the same rights of self-expression and self-determination afforded the rest of us.

Whatever their personal feelings on — or enjoyment of — pornography, few elected officials often see much benefit in taking a stand for the denizens of Porn Valley, fearing that a stand for sexual freedom or freedom of sexual expression might easily be portrayed as a disregard for violence, abuse and exploitation.

That's why the fight against pornography has always created strange bedfellows. During the “Sex Wars” of the 1980s, feminists such as Catherine MacKinnon and Andrea Dworkin aligned with social conservatives over the issue of pornography (indeed, after Dworkin’s death, The New York Times ran a collection of reminiscences from conservatives who’d bonded with her over a hatred of the sex industry) against sex-positive feminists such as Susie Bright and Carol Queen.

The anti-porn arguments laid out by four Republican members of Congress in a recent letter to Attorney General William Barr don’t sound all that different from the arguments many of Dworkin's liberal intellectual successors like Gail Dines have been making for years: it’s too easy to obtain, it promotes violence against women, it’s created a “public health crisis” and, of course, it’s destroying the minds of our children.

Still, even that's not new. About a decade ago, I sat in front of a classroom of New York University students as part of a panel discussion on the merits — and problems — of the modern pornography industry. Then, as a writer for the blog Fleshbot, which covered the industry, I’d been invited to make the case that pornography, though not wholly harmless, could certainly be a healthy part of human sexuality.

Sitting next to me was Pamela Paul, author of the 2005 book "Pornified: How Pornography Is Transforming Our Lives, Our Relationships, and Our Families." In Paul’s eyes, pornography — and internet pornography in particular — posed a serious threat to young people. The content online, she told students, wasn’t the innocent, "Playboy"-style fare of her youth, but a coarser, more vulgar form of obscenity. Children were going online and accidentally discovering extreme sex acts, she warned, and if we didn’t take action soon, things would only get worse.

Paul — now the editor of "The New York Times Book Review" — is hardly a Trump supporter, or even a conservative. Neither is Chyng-Feng Sun, an NYU professor and director of "The Price of Pleasure," a frequently-cited documentary that portrays pornography as fundamentally abusive and harmful to women, who also appeared on that panel to make a case against porn. But both of these women now find themselves, whether advertently or not, aligned with a contingent of the conservative movement who’ve recently stepped up attempts to get President Donald Trump — who ironically signed an anti-porn pledge as a candidate in 2016 — to take action against the supposed evils of porn.

But the liberal voices who’ve helped pave the way for the latest conservative assault on pornography might want to take a moment before further aligning themselves with this latest conservative cause. Because while panic about porn is an eternally bipartisan issue, it’s a partnership that rarely works out in liberals’ overall favor.

The political desire to censor, heavily regulate or ban pornography and criminalize adult industry rarely ends with that issue alone, because anti-porn conservatives are not one-issue conservatives. They see pornography as intimately connected to their larger "culture war" against all non-traditional relationships, gender identities and expressions of sexuality, and are keen on using it to build political coalitions to help advocate against abortion, LGBTQ rights, birth control and other forms of sexual freedom. (In the case of the new anti-pornography crusade, they appear to be building on the nascent alliance with anti-transgender so-called feminists.)

By giving the conservative movement broader credibility in their advocacy against pornography, liberals only serve to strengthen other assaults on sexual freedom, undermining their own beloved causes in the process.

Pornography is hardly a perfect industry, and there are many legitimate discussions to be had about how to improve the industry’s record on performer safety and ensuring that young people are not absorbing harmful messages about sex from material intended for adults. But liberals who care about these issues would be far better off engaging with the adult industry itself to develop solutions to those problems, rather than partnering with conservatives on a movement to censor, ban or otherwise further stigmatize pornography and sexual media.