Efforts to hijack the judiciary for political ends are hardly new. We have seen them throughout American history, and especially since the 1980s—though always restrained by a deeply held appreciation for the importance of protecting the courts’ credibility.

Until Donald Trump. Impelled by his own special blend of ignorance and indifference to the institutions that make democracy work, Trump has tweeted hard to discredit the judiciary, while simultaneously packing it with judges whose chief qualification appears to be ideological zealotry. That, and expected support for Trump’s caprices. Aided by his party in the Senate, the latest shenanigans around replacing Justice Ruth Bader Ginsburg—truly breathtaking in chutzpah and hypocrisy—signal a short-term “win at all costs” willingness to trash long-term judicial legitimacy that is unmatched in U.S. history. Undoing the damage may require strong measures to rehabilitate a once-storied judiciary now overstuffed with ideologues.

Some history is needed to understand how we got here. The judiciary is, in a weak sense, unavoidably political: Law is frequently indeterminate, which means judges must make choices, and their choices often have political consequences. This is particularly true for federal courts, and most of all the Supreme Court, whose every decision is political in this weak sense. Whether the judiciary is political in a stronger sense—viz, whether judges self-consciously make decisions to advance a political agenda—depends on who is on the bench, how the judges approach their duties, and whether the other branches push back.

In the early years of the republic, federal judges were unabashedly political: deciding cases based on party interests and writing opinions that were undisguised polemics. The Congress, controlled at the time by Thomas Jefferson’s Republican Party, finally impeached (brazenly Federalist) Justice Samuel Chase in 1804 for taking this behavior too far, and the deal that prevented his removal from the bench included an unspoken agreement that federal judges would assume the impartial role we idealize today.

That settlement held for most of American history, with some notorious departures. The Supreme Court tried to settle the issue of slavery in the territories in Dred Scott, worked hard to undo Reconstruction after the election of 1876, did its best to stymie progressive legislation in the early twentieth century and, later, to block the New Deal. In some instances, the Court was moving with the dominant political currents, in others it was swimming against the tide. In the latter cases, Congress and the executive pushed back—using or threatening to use tools the Constitution makes available for this purpose, including court packing, jurisdiction stripping, budget slashing, procedural revisions, and so on. In each instance, the Court eventually backed down.

The idea of “judicial supremacy”—that the Court has final say over the meaning of the Constitution—has been integral to the Court’s periodic bouts of strong political activism. The Jeffersonian demand that judges become less political was thus coupled with repudiating the Court’s claim to final authority over constitutional interpretation. That early struggle then set the pattern for the next 150 years, with “conservatives” (however defined by the politics of the moment) supporting aggressive claims of judicial supremacy to justify regulating politics, while “progressives” (however understood at the time) rebuffed them.

Then came the Warren Court. It was something new in the American experience: an activist Court that was also progressive. The left soon flipped, eagerly embracing the opportunities judicial intervention suddenly afforded to advance their agenda. Conservatives, for their part, continued to support judicial supremacy—objecting to what they saw as the Warren Court’s footloose method of interpreting the Constitution, but without denying that the Court’s word is final. The debate shifted from who has final say over the Constitution—the Court, everyone now agreed—to how that say should be exercised. Conservatives adopted a theory of interpretation based on “originalism,” while liberals stuck with a more open-ended, forensic approach that is sometimes called “living constitutionalism.”

As a practical matter, judicial supremacy was made operational by delegitimating the devices historically used by the political branches to push back—court packing, jurisdiction stripping, and the like. But given life tenure, limiting the available checks to the appointments process significantly augmented the Court’s ability to pursue an agenda. The role of the judiciary grew exponentially—an expansion that has continued uninterrupted whether the Court has been liberal (like the Warren Court), moderate (like the Burger Court), or conservative (like the Rehnquist and Roberts Courts).

Broad acceptance of judicial supremacy was a first step in moving courts in the direction of becoming political in the strong sense. A second step quickly followed, as political actors grasped the practical implications of supremacy. This was the step of centralizing the process for choosing nominees and vetting potential candidates for ideological conformity. Conservatives spotted this first, and the Reagan Administration moved aggressively to appoint judges who would further its political agenda.

The heightened stakes surrounding judicial appointments exploded publicly in the rancorous Robert Bork hearings in 1987. Republicans lost that battle, but they won the war. Today, no one bats an eye at the idea that judges are selected partly for their political allegiance and judicial ideology. Republicans have been far more energetic in these efforts than Democrats, who employ a similar playbook but have never been as attentive to the third branch.

Yet the politicizing of judicial appointments still had limits. Presidents might vet potential appointees for how they were likely to decide cases, and Senate support or opposition might likewise turn on a candidate’s perceived ideology, but both sides still cared about legal craft and acumen, and both insisted publicly on the importance of neutral legal principles. These requisites, in turn, had two meaningful effects. First, they helped sustain public support for the judiciary (which is significantly greater than for the other branches of government and, as striking, has until recently been nearly identical in both parties). Second, and more important, talking about the judiciary as principled rather than partisan limited the degree of politicization. Words matter, and habitual talk about fidelity to legal principle undoubtedly has an important influence in restraining the urge to become a full-throated partisan. So, too, has the practice of appointing mostly top tier legal technicians, for whom pride in craft is an important personal commitment.

Enter Trump, whose cluelessness about the norms and practices that constitute democracy is exceeded only by his disdain for their importance. Trump has dropped even the pretense of talking about judges as anything other than rank political agents—blathering nonchalantly about “Obama” judges, “Bush” judges, and “my” judges; vulgarly making clear that judges he appoints are supposed to rule in his favor; loutishly attacking rulings he dislikes as nothing more than anti-Trump bias; and openly mocking the very idea of an independent judiciary (which he sometimes puts in scare quotes in his tweets). Trump publicly handed judicial selection over to conservative partisans from the Heritage Foundation and Federalist Society, while cutting the non-partisan ABA out of the process. And while his decidedly ideological Supreme Court appointees have conventional resumes, the same cannot be said for his lower court nominations, which—a few genuinely accomplished lawyers notwithstanding—comprise a motley crew of ill-qualified partisan hacks.

Chief Justice John Roberts—a thoroughly conservative jurist who also cares about the credibility and future of a Court that will, after all, bear his name—has tried his best to mount a rearguard action. The Chief Justice’s efforts to prevent every high-stakes case from turning into a 5-4 decision along ideological lines have been gutsy (and clever), and his willingness to speak out is admirable. But it may be too little, too late, especially if Trump succeeds in replacing Justice Ginsburg with yet another partisan hack more interested in advancing the conservative political agenda than in either law or the legitimacy of the judiciary.

It’s too soon to say what the upshot will be. We’re saddled with a generation of second-rate judges, but whether Trump’s trashing of the last norms constraining outright partisanship on the bench outlasts him will depend on whether he gets a second term, how his successors respond, and how the public takes it all in.

Which may put the next administration in the ironic position of needing to deploy a blunt political tool—like court packing—to put an overly politicized judiciary back on course. As we learned decades ago from Anatol Rapaport and Robert Axelrod, once cooperation breaks down, the only play to restore it is tit-for-tat. Trump and the Republicans are unapologetic about discarding longstanding cooperative rules around making judicial appointments, first in refusing to approve Merrick Garland because legitimacy required waiting for an election that was close, and now in hypocritically cramming through a last-minute appointment lest they lose an election that’s even closer. If they win the election, none of this will matter. But should they lose, it becomes incumbent for Democrats to respond in kind. Tit for tat, hardball for hardball, is the only way to restore a less politicized regime for constructing a judiciary we can all respect.

If that seems paradoxical, perhaps we should say, as Oscar Wilde once did, “Well, the way of paradoxes is the way of truth.