In recent years, there has been a surge in energy behind the conservative argument that some forms of birth control are tantamount to abortion. Anti-choice activists have taken to saying that emergency contraception and IUDs work by “killing” fertilized eggs, a claim that is unsupported by science, which shows instead that these forms work by preventing sperm from meeting egg. Despite that, the Supreme Court ruled in Burwell v. Hobby Lobby that employers can use the abortifacient claim as a way to deny women birth control coverage, as long as the belief in the falsehood is sincerely held.

But is this belief that contraception equals abortion all that sincere, or has it been invented as a pretext to chip away at contraception access? In a new paper for the pro-choice Guttmacher Institute, senior policy communications associate Joerg Dreweke lays out a compelling case that the “belief” that some forms of contraception are abortion fluctuates based on political necessity. “Rather than applying the claim that some contraceptive methods in effect cause abortion consistently to all aspects of their advocacy,” Dreweke writes, “antiabortion groups ignore and often contradict their positions when it might hurt them politically.”

As Dreweke lays out, many major conservative organizations professed to believe that some forms of contraception are abortion when it came to protesting insurance coverage of contraception. “AUL [Americans United for Life] states that the policy is a ‘back door abortion mandate’ that requires employers to cover ‘life-ending drugs that have been deceptively labeled as contraception.’ SBA List also refers to the guarantee as an ‘Abortion Drug Mandate,’ while the Heritage Foundation says it requires ‘coverage of abortion-inducing drugs and devices,’” he writes. These organizations correctly gambled on the hope that most Americans wouldn’t worry too much about losing access to contraception. After all, most of us don’t work for Hobby Lobby and, worst case scenario, we can pay out of pocket if our employers cut us off.

But, as Dreweke continues, this deeply held belief that contraception is abortion dries up the second that belief scares the public into thinking access to contraception could be cut off entirely. Organizations like the Heritage Foundation have not demanded that abortion regulations be expanded to cover IUDs or emergency contraception, which they really should be doing if they sincerely think these things are abortion. These groups also put distance between themselves and groups that push “personhood” amendments, precisely because they don’t want the public to see them actively trying to ban these forms of birth control outright. After all, a ban on birth control is the likely result if you combine the belief that birth control “kills” fertilized eggs with a law requiring those fertilized eggs to be protected like persons. These groups also do not count IUDs or emergency contraception in the abortion statistics, an odd oversight if you sincerely believe these constitute abortion.

The hypocrisy is most evident when it comes to what kinds of birth control the anti-choice movement targets. The birth control pill and emergency contraception, after all, work exactly the same way: By tweaking your hormonal levels to prevent ovulation. Anti-choice groups, however, argue that emergency contraception makes the uterine lining unwelcoming to fertilized eggs. This isn’t true, but if it were, then birth control pills would have to do exactly the same thing, being exactly the same drug. But the Hobby Lobby lawsuit, for instance, ignored the birth control pill. Indeed, a popular talking point, heard all over Fox News, is that the lawsuit only addressed “four kinds” of contraception, an overt attempt to reassure women that more popular forms like the birth control pill were safe from attack.

“[M]ainstream antiabortion groups,” Dreweke writes, “appear to have long concluded that a frontal assault on the pill—the most popular reversible form of contraception, with more than 10 million current users—would be a sure political loser. That is why their attacks have focused on less commonly used methods, like IUDs and emergency contraceptives.” Belief in a contraception method’s abortive properties is inversely proportional to how popular it is.

All of this is in line with the anti-choice movement’s long-term incrementalist strategy, the one that has worked so well at chipping away abortion access. You take a little, not so much that the public gets alarmed, but enough to build on. Once they get used to that, you take away a little more. Work slowly and steadily enough and eventually people will find that they can’t get the reproductive health care they want. Trying to ban contraception outright or even just trying to stigmatize the birth control pill overtly would scare people too much right now, so instead the movement is warming us up slowly. It may take years of careful work before they can roll out the idea that the pill is “controversial,” but in the meantime, attacks on the IUD and emergency contraception at least get the public more used to the idea that there’s a “debate” over contraception.