The week began on a surprisingly strong note for reproductive justice advocates, as the US Supreme Court, by a 5–3 margin, overturned Texas’s draconian House Bill 2.

The law, which Wendy Davis famously filibustered in her pink tennis shoes, purported to protect women’s health by requiring that health clinics providing abortion services “meet the standards for ambulatory surgical centers, including regulations concerning buildings, equipment and staffing” and that “doctors performing abortions . . . have admitting privileges at a nearby hospital.” These regulations, which the Supreme Court found on Monday to be an “undue burden” for those seeking an abortion, would have shuttered half of the Texas facilities that perform abortions.

Activists are rightly celebrating the ruling as a win for abortion rights. In Texas and elsewhere, women seeking to terminate unwanted pregnancies likely won’t have to contend with the anti-abortion statutes passed since the 2010 Tea Party wave.

But the decision in Whole Women’s Health v. Texas, much like the 4–4 tie in the recent anti-labor Friedrichs v. CTA case, is more a reprieve than an absolute victory. Rather than overturn an earlier, poorly decided decision, the Court potentially locked in the justification for restricting the unalloyed right to an abortion by ruling that the Texas law was simply an overreach.

That earlier, poorly decided case, 1992’s Planned Parenthood v. Casey, represented the culmination of the Reagan-Bush-era legal drive to overturn Roe v. Wade. In a 5–4 decision, in which Anthony Kennedy cast the decisive vote, the Court upheld a Pennsylvania law that mandated a twenty-four-hour waiting period, parental consent for minors, and spousal notification before a woman could obtain an abortion.

While the ruling nominally rendered Roe v. Wade a settled precedent (Antonin Scalia and Clarence Thomas voted against it for that reason), it opened the door for state law restrictions, as long as they didn’t present a “substantial obstacle in the path of a woman seeking an abortion before the fetus attains viability.” In other words, Casey simultaneously protected the right to an abortion and gutted it.

This is strikingly similar to how the Supreme Court has handled labor rights. In 1937, Congress passed the National Labor Relations Act, which enshrined workers’ right to form unions and go on strikes, and gave the federal government the power to go after bosses who interfered with those rights.

But one year later, a key Supreme Court decision, which was similarly celebrated at the time, protected the right to strike while utterly gutting it. In Mackay Radio v. NLRB, the Court upheld the law and ordered the employer to reinstate four striking workers who had been fired.

Yet despite the statute’s guarantee that “Nothing in the Act should be interpreted to interfere with or impede or diminish in any way the right to strike,” as well as its explicit protection of striking workers against “discrimination,” the Court held that in order to “protect and continue his business,” the boss could permanently replace workers in the order of reserve seniority. Employers, in other words, could get rid of striking workers as long as it didn’t present a substantial obstacle to exercising their union rights.

Obsessive union-busters seized on the new precedent. In one important case, an employer tried to give its scabs “super-seniority” — workers who had gone on strike would get laid off first, even years after the job action. The Court struck down that action in 1963, ruling that it was too discriminatory and “not proper under Mackay.” But like Whole Women’s Health, the Court’s Erie Resistor decision further legitimized restrictions on a fundamental right by declaring that a certain set of actions simply went too far — not that the right was improperly restricted in the first place.

A ticking time bomb for decades, the so-called Mackay Doctrine was deployed by employers in the 1980s and 1990s as part of a broader union-busting campaign. Beginning with a strike at the Phelps-Dodge mining corporation in 1983, employers bargained hard for drastic concessions in pay, benefits, and working conditions; dared their unions to strike; hired scabs to take their jobs; and after twelve months encouraged the replacement workers to vote to decertify the union. This is the union-busting playbook that has decimated labor’s ranks and paved the way for massive income and wealth inequality.

Casey has worked out about as poorly for reproductive rights advocates.

The past quarter century has seen a sustained drive to place all kinds of limits on reproductive rights: waiting periods, forced “counseling,” trans-vaginal ultrasounds, burdensome zoning regulations. Already more than a third of women seeking an abortion have to travel at least twenty-five miles to find a facility. Add in mandatory waiting periods (still constitutional, alas), and you’re talking about entire days off from work, travel and motel expenses as well as the cost of the procedure itself, which is often not covered by insurance. (Now, as ever, is an excellent time to donate to your local abortion access fund.)

For far too many working-class women, the right to an abortion exists on paper, rather than as a genuine right — just as for many workers, the right to strike remains purely formal.

So by all means, let’s breathe a sigh of relief. Let’s take some time to celebrate. This was supposed to be a much worse Supreme Court term, and maybe, just maybe, we’re seeing the beginning of the end for constitutionally accepted restrictions on abortion rights.

But the labor movement’s experience with Mackay should give us pause. Even if the heat dies down on new anti-choice efforts, if the now-legitimized Casey precedent is not overturned, and soon, it could be used as legal ammunition in the next massive assault on reproductive rights.

The next president could appoint as many as three Supreme Court justices — totally changing the high court’s makeup and voting dynamics. We need to begin thinking beyond the defensive strategies of Friedrichs and Whole Women’s Health and start planning campaigns of judicial activism to overturn rotten Court precedents and put women’s fundamental rights on firmer legal footing.

[This article originally appeared at Jacobin.]