No one can shape American society — for good or for ill — quite like federal judges. Regressive moves by the courts in recent years have illustrated their awesome power to gut the Voting Rights Act, open the floodgates to political campaign funders, and give companies the right to refuse covergae of their employees’ birth control. Yet we’ve also seen federal judges serve as a critical bulwark against President Trump’s attempts to circumvent environmental rules, declare a national emergency in order to fund a border wall, and ban travelers from predominantly Muslim countries.

The federal judiciary is, of course, meant to serve as a check on the power of the presidency and Congress. That’s why the astounding scale of Trump’s remaking of it is cause for significant alarm. It’s both a resounding reminder that elections have consequences — 2016’s has already done long-run damage to our democracy — and that a single election is not enough to recover. No matter what happens in November, the breadth of the Donald Trump legacy on the federal courts, aided and abetted by a slim Republican Senate majority, will be with us for decades to come.

The numbers alone are staggering. In the pre-holiday rush to recess, Senate confirmations brought to 187 the number of Trump-appointed judges now on the bench, a full 20 percent of the entire federal judiciary in under three years. Trump has named more than a quarter of all appeals court judges — important because their word will be the final one on thousands of cases involving critical policy issues (except for the 150 or fewer cases accepted by the Supreme Court each year). Think immigration, political corruption, civil rights.

The pace of those nominations now rubber-stamped in the Senate is virtually unprecedented. During the first three years of his presidency, Trump has already named 50 appeals court judges (with two nominations pending). By contrast, President Obama had named 24 in that same time frame.

Also alarming is the willingness of Trump and Senate Republicans to ignore the wisdom of the American Bar Association evaluations, which have given rare “Not Qualified’’ ratings to nine nominees, two of whom were confirmed for these lifetime appointments in the past month.

The potential for partisanship is already apparent. The Supreme Court (which has two Trump appointees) recently agreed to hear three cases involving which records the sitting president has to turn over to congressional investigators or to Manhattan District Attorney Cyrus Vance Jr. A decision from the US Court of Appeals for the D.C. Circuit on a House subpoena of some of Trump’s financial records is one of them, and it’s instructive. The 2-1 decision, written by Judge David Tatel, a Democratic appointee, found the congressional committee’s interest in alleged illegal conduct is in “furtherance of its legislative purpose.’’

However, newly named Trump appointee Neomi Rao wrote in dissent: “Allowing the committee to issue this subpoena for legislative purposes would turn Congress into a roving inquisition over a co-equal branch of government.’’

Not all Trump appointees will turn out to be partisans or Trump sycophants. Many come to the court with impressive resumés, judicial clerkships, or extensive experience in the legal community or academia. And then there is Judge Lawrence VanDyke, confirmed for the Ninth Circuit Court of Appeals earlier this month despite a Not Qualified rating from the ABA. An ABA evaluator’s report was based on 60 interviews, including 43 lawyers, 16 judges, and another person who worked with VanDyke in four states in which he practiced. It read, in part:

“Mr. VanDyke’s accomplishments are offset by the assessment of interviewees that Mr. Van Dyke is arrogant, lazy, an ideologue, and lacking in knowledge of the day-to-day practice including procedural rules. There was a theme that the nominee lacks humility, has an ‘entitlement’ temperament, does not have an open mind, and does not always have a commitment to being candid and truthful.’’

VanDyke was confirmed 51-44.

Also earning an ABA Not Qualified rating was Sarah E. Pitlyk, a former law clerk of Supreme Court Justice Brett M. Kavanaugh when he was a federal appellate court judge, and recently confirmed 49-44. The ABA questioned her lack of experience, noting she has “never tried a case as lead or co-counsel, whether civil or criminal.’’ Nor has she ever taken a deposition or argued a motion in state or federal court. But she did write a number of spirited defenses of Kavanaugh’s record during his own contentious confirmation hearings. She also coauthored an amicus brief opposing California’s protections for assisted reproductive technology, insisting that “the practice of surrogacy has grave effects on society, such as diminished respect for motherhood and the unique mother-child bond.’’

Another Kavanaugh clerk confirmed this fall (50-41), also despite his Not Qualified rating from the ABA, was Justin R. Walker, now sitting on the US District Court in Kentucky. Again the ABA cited his lack of experience (less than 10 years since his law school graduation), especially “the absence of any significant trial experience.’’

Some observers insist — without evidence — that the ABA has a liberal bias, but this is not borne out by the data.

The bias is instead on the part of Trump. He is truly remaking the federal courts in his own image — two-thirds of confirmed judges are white and male, albeit far younger than the sitting president. Some 86 percent of all confirmed judges are white — in a country that is 76.5 percent white.

There was a time when arcane Senate rules and longstanding tradition served to sideline marginal candidates for judgeships. The “blue slip’’ tradition, which gave home-state senators enormous power to delay or even scuttle a nominee they didn’t approve of, is now truly a thing of the past. So too the use of the filibuster, which at least meant that nominees had to get 60 votes in the Senate to win confirmation; now they need only 51.

Imagine for a moment a second-term Trump with even fewer guardrails and the ability to dole out lifetime appointments like so many candy canes at Christmas — unless, of course, there’s a turnaround in the Senate.

The stakes are high for the Republic and for the rule of law in the 2020 election. The Democratic presidential candidates, for their part, have not done nearly enough to explain the long-term consequences this election will have on the judiciary and hence for the separation of powers in our democracy. It should be among their most urgent calls for change in the White House. For if we fail on that score, we will be failing ourselves and the next generation.