In the wake of President Trump’s pardon of Arizona Sheriff Joe Arpaio, reporters are likely to hear words as harsh as “disturbed” and “concerned“ floated by anonymous leaders of the president’s party on Capitol Hill.

There will be few if any leaks from the Supreme Court. But one must wonder what messages the justices are getting from Trump’s extraordinary pardon. Though its major import is Trump’s official endorsement of racist discrimination in law enforcement, a flagrant contempt for judges and courts is the subtext. The issue in the Arpaio case was the very integrity of the federal judiciary. He was not convicted of an ordinary crime, but of deliberately disobeying a federal court order and lying about that; but beyond that, during the litigation that led to his conviction for criminal contempt, he hired a private detective to investigate the wife of a federal judge hearing a case against his office. Any judge can understand the threat posed by law enforcement personnel who seek to strike back at judges and their families, perhaps for purposes of blackmail or revenge—and the deep arrogance of a president who regards such behavior as praiseworthy.

In fact, since even before the election, Trump has brandished his hostility to judges almost as aggressively as his disregard of racial decency. When federal district Judge Gonzalo Curiel was assigned the Trump University civil fraud case, Trump attacked the Indiana-born Curiel in front of a campaign rally as “Mexican” and “a total disgrace.” When Judge James Robart (a George W. Bush appointee) of the District of Washington enjoined the first version of Trump’s “travel ban,” Trump on Twitter dismissed Robart as a “so-called judge" and told his supporters “If something happens blame him and court system.”  When another District Judge enjoined his “sanctuary cities” defunding order, Trump publicly threatened to break up the Ninth Circuit. When a terror cell carried out a car attack in Barcelona earlier this month, Trump immediately zeroed in on the “travel ban” case, now pending before the Supreme Court: “The courts must give us back our protective rights,” he tweeted.

Every indication is that Trump will respond to an adverse Supreme Court ruling on any important issue with a full-throated assault on the court and on the very idea of judicial independence. That the court’s majority is conservative and Republican won’t matter. Sen. Mitch McConnell can testify to Trump’s lack of respect for his fellow Republicans; and for that matter so can Chief Justice John Roberts, whom Trump dismissed during the election campaign as “an absolute disaster” because of his vote upholding the “individual mandate” portion of the Affordable Care Act.

Supreme Court justices live in a different world than most of us. They are protected by life tenure, and swaddled in a day-to-day environment as obsequious as the biblical court of Nebuchadnezzar. They are rarely racially profiled at traffic stops, set upon by chanting thugs with tiki torches, or run over by cars at political protests. Ordinary citizens may feel the changing winds of politics more quickly and keenly than justices.

Yet politics, in somewhat distorted form, makes its way into their protective cocoon sooner or later. Is it possible that the Arpaio pardon will be the moment that the conservative justices, or some of them, realize that this is not an ordinary administration, and that the cases coming before them this fall have higher than ordinary stakes?

Judges are usually expected to put aside the present political meaning of legal issues—will this decision help my party or the other party?—and consider them under the gaze of eternity. Administrations come and go, the theory says; decisions about the meaning of statutes or the scope of presidential authority may persist long after this issue has been forgotten. The issue thus should ordinarily not be, “Will this help or hurt Trump?” but “In the long run, which conforms better to the wording of a statute or the structure of the Constitution?”

But what if the issue behind present cases is whether, four or ten years hence, we will have a Constitution or a self-governing republic at all? How clear would those stakes have to be before the justices will decide that they may be the only emergency brake cord in a government threatening to jump the tracks?

History isn’t encouraging. Judges frequently like to roar from the bench about their independence and high-mindedness; but when it comes to true independence, these lions of the law often turn cowardly. Times of war and emergency make them even more timorous. The court enthusiastically backed Woodrow Wilson’s World War I crackdown on civil liberties; it meekly surrendered to the Japanese Internment. In two Nixon-era cases, the court held that media outlets could publish the formerly secret Pentagon Papers, and that Nixon had to turn over the “smoking gun” tape to a federal court. But those decisions, historically, are anomalous.

Much more typical is the rhetorical switcheroo played by the court in Ziglar v. Abbasi last term. The plaintiffs in that case were improperly documented aliens who were snatched off the street after the 9/11 attack and held for months even though there was no evidence linking them to terrorism. High-ranking officials at the Department of Justice ordered them held unlawfully, and instructed that the conditions be “restrictive”—which in practice meant solitary confinement, beatings, and lack of sleep. Sixteen years later, they were still seeking a chance to make their case against the higher-ups who authorized the mistreatment. The court’s majority threw out their case. Justice Anthony Kennedy’s opinion contained the obligatory preen: “Nothing in this opinion should be read to condone the treatment to which [the plaintiffs] contend they were subjected.” But at its heart, the opinion’s concern ran entirely toward the powerful: the great danger would be a decision that would “chill the interchange and discourse that is necessary for the adoption and implementation of governmental policies.”

If the Ziglar opinion is defensible at all (in case it’s not obvious, I side with Justice Stephen Breyer, along with Justice Ruth Bader Ginsburg, who dissented), it is defensible as an exercise of that “what if?” vision I mentioned above. That is, assuming the republic survives, should future executive officials have to worry about being sued when they make emergency decisions?

But increasingly, the question for the court—as for Congress, and for the country—is whether the republic survives not against external threat but against an unprecedented unremitting internal assault. A sense of proportion is necessary in crisis and calm; and even in the midst of shocking official misbehavior, the Arpaio pardon crosses a line. Trump has made it clear that the limits of the law, and the powers of the courts, hold no weight in his decision-making, and indeed will be brushed aside at his convenience.

Will the justices strike back, or shake a feeble fist and warn that they'll really do something one of these days?