The U.S. Department of Justice sued the state of Texas on Thursday, arguing that SB8 — the so-called heartbeat statute that bans abortion after six weeks of pregnancy — violated the Constitution and is preempted by federal law. The complaint could be just the tip of the iceberg when it comes to the federal response to the unusual Texas statute.

Texas’s law resembles other heartbeat bills, which criminalize abortions performed when a doctor can detect fetal cardiac activity. But there is one key difference: Texas outsources enforcement to private citizens (any private citizen) who can sue abortion providers or those who “aid or abet” them and receive a minimum of $10,000 in damages for each abortion in violation of the law. The state’s law was based on a model created in Waskom, Tex., a town of less than 2,000 people near the Louisiana border. Mark Lee Dixon, a Southern Baptist pastor and ardent opponent of abortion, had read a news article from the early 1990s suggesting that a pro-choice donor stood ready to buy land and build a clinic in Waskom if Louisiana shut down its facilities.

Waskom passed a law to prevent this (remote) possibility, banning abortion and allowing private citizens to sue to enforce the law. Soon, similar sanctuary-city-like movements had spread across Texas and beyond.

In enacting SB8, Texas relied on a doctrine called sovereign immunity to protect itself from legal challenges. Individuals can enforce their constitutional rights only against the government and its agents, and the 11th Amendment to the Constitution has been interpreted to limit when someone can sue a state government. In 1908, in a decision called Ex parte Young, the Supreme Court created an exception to this rule for people suing state officials charged with enforcing an unconstitutional law. But for SB8, there is a catch: The Texas law allows only private individuals to sue and prohibits state officials from enforcing the law.

So when abortion providers, who questioned the constitutionality of SB8 (which clearly bans abortion before viability in contravention of Roe v. Wade), sued to attempt to block it, they named as defendants a group of state officials, judges and a single antiabortion activist.

Providers argued that the state officials, judges and activist would enforce the statute’s unconstitutional provisions. A trial judge temporarily enjoined SB8 while litigation unfolded, but the Fifth Circuit Court of Appeals put a halt to proceedings in the district court, ruling that state officials were the wrong targets of the lawsuit. The providers then asked the Supreme Court for an emergency order to stop SB8, but last week, the high court let the Texas law go into effect. While not weighing in on the constitutionality of the law, a majority of the justices said that the providers had not proved that they had found the right defendants to sue — and that the state might have immunity after all.

The Biden administration did not take long to react, vowing a “whole of government” response to Texas’s bill. The Justice Department complaint came Thursday in federal district court, claiming authority to “ensure that Texas cannot evade its obligations under the Constitution.” Specifically, the department argues that the federal government is charged with ensuring protection of constitutional rights, and the Texas law seeks to impede that duty. The complaint does not stop there, arguing further that Texas violates federal law “by purporting to prohibit federal agencies from carrying out their responsibilities under federal law,” exposing federal employees to potential lawsuits under SB8 and stopping federal employees from performing abortions in cases of rape or incest.

At first, the complaint seems to underscore the limits of the federal government’s power to respond to Texas. A doctrine called standing, or locus standi, limits who can bring a claim in federal court. The Supreme Court has held that at a minimum, someone with standing must have an actual or threatened injury, traceable to the person being sued, that could be cured by a favorable court decision.

And the federal government might not meet that standard. The complaint argues that the Biden administration must vindicate the rights of women and doctors because Texas has blocked them from doing so themselves. But even if the administration is right that Texas “has acted in open defiance of the Constitution,” that doesn’t mean that the government has suffered the kind of harm required to have standing in federal court. The Fifth Circuit (and, ultimately, the Supreme Court) could respond that the kind of harm alleged by the United States — being unable to protect a Texan’s right to have an abortion, for example — is too abstract. And since no private citizen has yet tried to collect damages under the law, it is not clear that the Justice Department has anyone to hold accountable for enforcing the unconstitutional law.

What’s remarkable about the complaint, though, is not necessarily its chances of success. It’s the first time the Justice Department has intervened to enjoin a state abortion restriction, period, not just the first time it’s done so with arguments grounded in principles of federalism. That said, before Texas, no state had ever successfully enacted an unconstitutional law that made its enforcement mechanism — private citizens suing for money damages — a shield against court scrutiny.

So the Justice Department’s willingness to intervene against Texas spotlights new terrain in the abortion debate. In the course of outlining how various federal government agencies and programs touch on abortion care (such as those provided in federal prisons or to federal employees), the brief makes plain the many ways in which abortion features in federal law. The U.S. government could stake out places and supply personnel for abortion provision, governed by federal laws, that are not subject to state restrictions or, for that matter, to lawsuits under laws like SB8. Federal employees would be immune from lawsuits commenced by private citizens.

The suit is also a reminder that the federal government could proactively protect abortion rights for the same reasons it argues that the Texas law must fall: Federal regulation trumps state regulation. Under constitutional principles that accord federal law supremacy, the federal government could do a lot to preserve and expand abortion rights even in the face of newfound efforts to restrict them in Republican-controlled states. Congress could, of course, pass a law like the Women’s Health Protection Act, which is before both the House and Senate but is unlikely to make its way past a potential GOP filibuster. The bill would create a statutory right to abortion and seeks to preempt most of the restrictions on state lawbooks now.

Federal agencies, like the U.S. Food and Drug Administration, also could play a role — which wouldn’t require navigating bipartisan abortion politics. The FDA is presently reconsidering the rules governing medication abortion that require in-person dispensation and prohibit pharmacies from stocking the two-drug regimen. This week’s events suggest that the Biden administration, galvanized by the extraordinary events in Texas, may abandon some of its previous reticence to support abortion rights. If the FDA permits abortion pills to be mailed to patients or to be picked up at a pharmacy, early abortion (before 10 weeks of pregnancy) will be portable and cheaper. Each time a federal agency or the executive branch acts to extend abortion rights, the question of whether those actions overrides state laws to the contrary becomes live.

Ultimately, even if the lawsuit against Texas fails, the Biden administration has sent a message to Texas and other copycat states with action and not just words. That matters because the federal government could be a powerful facilitator of abortion care if the Supreme Court abandons a nationwide constitutional right to abortion. By the end of this term, the Supreme Court will decide whether bans on abortion before viability, such as SB8, are constitutional. If the justices give states the green light to restrict abortion throughout pregnancy, already scarce abortion services in the South and Midwest will probably cease to exist as states enact near-total bans. But coordinated federal activity, buoyed by an already well-mobilized movement for abortion access, could close the gaps in coverage.

When so much about abortion seems to hinge on the Supreme Court, it’s easy to believe that the fate of abortion rights turns on judges alone. But the opposite may be true. The Roe v. Wade decision did not come down in a vacuum; it was part of a much broader story of grass-roots mobilization and legislative organizing. If, as many expect, the Supreme Court reverses Roe, that opinion will have its own grass-roots history — decades of work by the antiabortion movement to attack judicial overreaching and popularize fetal rights. Officially, the Supreme Court pays no attention to politics or popular opinion. Unofficially, it’s much more complicated. The court rarely strays too far from public opinion, at least not without facing a significant backlash.

Texas’s law certainly reflects the work of some true believers. But there is no shortage of politicians — including some of the red-state governors positioning themselves for a presidential run in 2024 — who gravitate to abortion bans mostly because they will expect them to pay off politically. Polls tell us that most Americans favor restrictions on abortion but oppose early abortion bans — and they want Roe v. Wade to remain the law. That hardly matters if only abortion opponents donate and vote based on the issue.

Win or lose, by filing this complaint, the administration is lending its voice to those opposed to Texas’s law — a chorus that supporters of abortion rights hope will eventually become too loud to ignore. By joining the opposition to SB8, the federal government signals that it will respond to the political fallout and outrage expressed at Texas and the Supreme Court. What happens to abortion in America has always depended on political mobilization. No Supreme Court decision can change that.