The next front is rapidly emerging in the struggle between supporters and opponents of legal abortion, and that escalating conflict is increasing the chances that the issue will shape the 2024 election as it did last Novembers midterm contest.

President Joe Biden triggered the new confrontation with a flurry of recent moves to expand access to the drugs used in medication abortions, which now account for more than half of all abortions performed in the United States. Medication abortion involves two drugs: mifepristone followed by misoprostol (which is also used to prevent stomach ulcers). Although abortion opponents question the drugs safety, multiple scientific studies have found few serious adverse effects beyond headache or cramping.

Federal regulation of the use and distribution of these drugs by agencies including the FDA and the United States Postal Service has long been overshadowed in the abortion debate by the battles over Supreme Court nominations and federal legislation to ban or authorize abortion nationwide. But with a conservative majority now entrenched in the Court, and little chance that Congress will pass national legislation in either direction any time soon, abortion supporters and opponents are focusing more attention on executive-branch actions that influence the availability of the pills.

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The reality of abortion care has been changing very, very rapidly, and now the politics are catching up with it, Celinda Lake, a Democratic pollster who served as one of Bidens advisers in 2020, told me.

Tens of thousands of anti-abortion activists will descend on Washington today for their annual March for Lifethe first since the Supreme Court last summer overturned Roe v. Wade, the 1973 decision that established a nationwide right to abortion. The activists will cheer the swift moves by some two dozen Republican-controlled states to ban or severely restrict abortion since the Court struck down Roe.

But even as abortion opponents celebrate, they are growing more frustrated about the increased reliance on the drugs, which are now used in 54 percent of U.S. abortionsup dramatically from less than one-third less than a decade ago, according to the Guttmacher Institute, a research group that supports abortion rights. With the overturning of Roe, [with] COVID, and with President Bidens loosening of the restrictions on these [drugs] there is a new frontier that everyone is pivoting to, Rebecca Parma, the legislative director for Texas Right to Life, a prominent anti-abortion group, told me.

George W. Bush and Donald Trump, the two Republicans who have held the presidency since the drugs were first approved under Democratic President Bill Clinton, in 2000, took virtually no steps to limit their availability. But conservative activists are already signaling that they will press the Republican presidential candidates in 2024 for more forceful action.

Our job is to make sure this becomes an issue that any GOP candidate will have to answer and address, Kristan Hawkins, the president of the anti-abortion group Students for Life of America, told me. No one can be ambivalent again; it will simply not be an option.

The challenge for Republicans is that the 2022 midterm elections sent an unmistakable signal of resistance to further abortion restrictions in almost all of the key swing states that tipped the 2020 presidential election and are likely to decide the 2024 contest. Would you really want to be Ron DeSantis or Donald Trump running in a close election saying, Im going to ban all abortion pills in Michigan or Pennsylvania right now? says Mary Ziegler, a law professor at UC Davis, who has written extensively on the history of the abortion debate.

Sunday is the 50th anniversary of the original Roe decision, and the Biden administration will mark the occasion with a defiant pro-abortion-rights speech from Vice President Kamala Harris in Florida, where GOP Governor DeSantis, a likely 2024 presidential contender, signed a 15-week abortion ban last April.

White House officials see access to abortion medication as the next battlefront in the larger struggle over the procedure, Jennifer Klein, the director of the White House Gender Policy Council, told me. She said she expects Republicans to mount more sweeping efforts to restrict access to the drugs than they did during the Bush or Trump presidencies. The reason youve seen both Democratic and Republican administrations ensure access to medication abortions is because this is the FDA following their evidence-based scientific judgment, she said. So what I think is different now is you are seeing some pretty extreme actions as the next way to double down on taking away reproductive health and reproductive rights.

Federal regulation of the abortion drugs has followed a consistent pattern, with Democratic presidents moving to expand access and Republican presidents mostly accepting those actions.

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During the 2000 presidential campaign, for instance, George W. Bush called the Clinton administrations initial approval of mifepristone wrong and said he worried it would lead to more abortions. But over Bushs two terms, his three FDA commissioners ignored a citizen petition from conservative groups to revoke approval for the drug. Under Barack Obama, the FDA formalized relatively onerous rules for the use of mifepristone. Physicians had to obtain a special certification to prescribe the drug, women had to meet with their doctor once before receiving it and twice after, and it could be used only within the first seven weeks of pregnancy.

The FDA loosened these restrictions during Obamas final year in office. It reduced the number of physician visits required to obtain the drugs from three to one and increased to 10 the number of weeks into a pregnancy the drugs could be used. The revisions also permitted other medical professionals, such as nurses, to prescribe the drugs if they received certification, and eliminated a requirement for providers to report adverse effects other than death. Trump didnt reverse any of the Obama decisions. He did side with conservatives by fighting a lawsuit from abortion-rights advocates to lift the requirement for an in-person doctors visit to obtain the drugs during the COVID pandemic. But by the time the Supreme Court ruled for the Trump administration in January 2021, Biden was days away from taking office. Within months, women seeking an abortion could consult with a doctor via telehealth and then receive the pills via mail.

On January 3 of this year, the FDA took another major step by allowing pharmacies to dispense the drugs. In late December, the Justice Department issued a legal opinion that the Postal Service could deliver the drugs without violating the 19th-century Comstock Act, which bars use of the mail to corrupt the public morals.

The paradox is that the impact of these rules, for now, will be felt almost entirely in the states where abortion remains legal. Obtaining abortion pills there will be much more comparable to filling any other prescription. But 19 red states have passed laws that still require medical professionals to be present when the drugs are administered, which prevents pharmacies from offering them despite the FDA authorization. And although the FDA has approved use of mifepristone for the first 10 weeks of pregnancy, medical professionals cannot prescribe the drugs in violation of state time limits (or absolute bans) on abortion. In terms of anti-abortion states, the Biden administrations actions have had basically no impact, Greer Donley, a University of Pittsburgh law professor who studies abortion law, told me in an email.

Although the red states have largely walled themselves off from Bidens efforts on medication abortion, conservatives have launched a multifront attempt to roll back access to the pills nationwide. Students for Life has filed another citizen petition with the FDA, arguing that doctors who prescribe the drugs must dispose of any fetal remains as meical waste. In a joint letter released last week, 22 Republican attorneys general hinted that they may sue to overturn the new FDA rules permitting pharmacies to dispense the drugs. In November, another coalition of conservative groups filed a lawsuit before a Trump-appointed judge in Texas seeking to overturn the original certification and ban mifepristone. Jenny Ma, the senior counsel at the Center for Reproductive Rights, says that decision could ultimately have a broader effect than even the Supreme Court ruling overturning Roe: This case, she told me, could effectively ban medication abortion nationwide. It means people in every state may not be able to get abortion pills.

Republicans will also ramp up legislative action against the pills, although their proposals have no chance of becoming law while Democrats control the Senate and Biden holds the veto pen. Republican Senator Cindy Hyde-Smith of Mississippi is planning to reintroduce her SAVE Moms and Babies Act, which would restore the prohibition against dispensing abortion drugs through the mail or at pharmacies.

From the May 2022 issue: The future of abortion in a post-Roe America

However these legal and legislative challenges are resolved, its already apparent that the 2024 GOP presidential field will face more pressure than before to propose executive-branch actions against the drugs. Thats going to be our clarion call in 2024, says Kristi Hamrick, a long-term social-conservative activist, who now serves as the chief strategist for media and policy at Students for Life.

Katie Glenn, the state-policy director at Susan B. Anthony Pro-Life America, told me that, at the least, the group wants 2024 Republican presidential candidates to press for restoring the requirement to report adverse consequences from the drugs. Former Vice President Mike Pence, a likely candidate, has already suggested that he will support a ban on dispensing the pills through the mail. But the anti-abortion movements long-term goal remains the same: ban mifepristone altogether. Hawkins shows the growing fervor GOP candidates will face when she says, This pill is a cancer that has now metastasized throughout our country.

Simultaneously, abortion-rights advocates are pushing the Biden administration to loosen restrictions even further. Medication abortion has been overregulated for far too long, Ma told me. Many advocates want the FDA to extend permitted use of mifepristone from 10 to 12 weeks, eliminate the requirement that the professionals prescribing the drugs receive a special certification, and begin the process toward eventually making the drug available over the counter.

The immediate question is whether the Biden administration will challenge the red-state laws that have stymied its efforts to expand access. Advocates have argued that a legal case can be made for national FDA regulations to trump state restrictions, such as the requirement for physicians to dispense the drugs. But Biden is likely to proceed cautiously.

We dont have a lot of answers because, frankly, states have not tried to do this stuff in hundreds of years, Ziegler, the author of the upcoming book Roe: The History of a National Obsession, told me. Even so, she added, its a reasonable assumption that this conservative-dominated Supreme Court would resist allowing the federal government to preempt state rules on how the drugs are dispensed.

These mirror-image pressures in each party increase the odds of a clear distinction between Biden (or another Democrat) and the 2024 GOP nominee over access to the drugs. Democrats are generally confident they will benefit from almost any contrast that keeps abortion prominent in the 2024 race. Some, like Lake, see access to the pills as a powerful lever to do that. The issue, she argues, is relevant to younger voters, who are much more familiar than older people with the growing use of medication abortion and are especially dubious that pharmacies can offer certain drugs in some states but not in others.

The impact of abortion on the 2022 election was more complex than is often discussed. As Ive written, in the red states that have banned or restricted the practice, such as Florida, Ohio, and Texas, there was no discernible backlash against the Republican governors or state legislators who passed those laws. But the story was different in the blue and purple states where abortion remains legal. In pivotal states including Arizona, Michigan, Pennsylvania, and Wisconsin, a clear majority of voters said they supported abortion rights, and, according to media exit polls, crushing majorities of them voted against Republican gubernatorial candidates who pledged to restrict abortion. Those Democratic victories in the states likely to prove decisive again in 2024 have left many Republican strategists leery of pursuing any further constraints on abortion.

Whats clear now is that even as abortion opponents gather to celebrate their long-sought toppling of Roe, many of them wont be satisfied until they have banned the procedure nationwide. It is totally unacceptable for a presidential candidate to say, Its just up to the states now, Marilyn Musgrave, the vice president for government affairs at the Susan B. Anthony group, told me. We need a federal role clearly laid out by these presidential candidates. Equally clear is that abortion opponents now view federal regulatory actions to restrict, and eventually ban, abortion drugs as a crucial interim step on that path. The U.S. may seem in some ways to be settling into an uneasy new equilibrium, with abortion banned in some states and permitted in others. But, as the escalating battle over abortion medication makes clear, access to abortion in every state will remain on the ballot in 2024.