The Constitution grants federal judges life tenure, subject only to impeachment if they fail to exhibit “good behavior.” Alexander Hamilton described it as “permanent tenure of judicial offices.” Progressives who hate the current conservative dominance of the Supreme Court think they have found a way around that provision. Congress would just create a new kind of judicial office. It would include the full powers of the Supreme Court, as we know them, for 18 years but more limited powers afterward.

Sen. Sheldon Whitehouse (D-R.I.) and eight of his colleagues have sponsored legislation to create these offices. It says nothing about exempting the current justices. Presidents would nominate new justices every two years and, as they did so, the most senior justices would be demoted, no longer able to vote in the vast majority of cases. Justice Clarence Thomas would be the first to be affected by the new rules, followed by Chief Justice John G. Roberts Jr. and Justice Samuel A. Alito Jr.

But redefining the office doesn’t overcome the constitutional obstacle to term limits. Applying the bill to a sitting justice would mean, effectively, revoking his current office and appointing him to a new one. He would no longer have life tenure in the office to which a president had nominated him and the Senate had confirmed him.

Progressives who have gone along with the idea that Congress has the power to regulate the justices in this way should think about the implications. Republicans could win the presidential election and control of both houses of Congress this fall. Adam J. White, a conservative colleague of mine at the American Enterprise Institute who served on Biden’s commission on court reform, has already imagined how a ruthless Republican government could use the power that the Democrats’ constitutional theory offers them.

If a statute can remodel the justices’ offices, then Republicans would have the power to neuter the most recently appointed justice instead of the most senior one while appointing their own pick. They could, that is, strip Justice Ketanji Brown Jackson, Biden’s appointee, of the power to vote in crucial cases, and thus convert the 6-3 conservative majority into a 7-2 one. It would be just as constitutionally faithful a move as the one Democrats are considering.

And then, of course, a future president and Congress could reshuffle the jobs again, restoring the powers of previously weakened justices and enfeebling a different set of them. Liberals could ultimately come out on top, or conservatives could, or the courts could stay in radical flux forever. Who knows? The effect on the rule of law and public confidence in it is easier to predict.

There are two fixes that might make the term-limit idea constitutional. One would be to apply the limit to sitting justices but do it via constitutional amendment instead of statute. The other would be to stick with a statutory change and exempt the current justices.

But where’s the fun in any of that for progressives? Calling for a constitutional amendment is almost always pure symbolism. Democrats are not going to get three-quarters of the states to agree to destroy the conservative majority on the Supreme Court. A statute that limits only future justices, meanwhile, is a kind of unilateral disarmament in the judicial wars. If a hypothetical President Harris worked with a Democratic Congress to adopt the idea, they would be making their own appointees less powerful than the current justices. That’s no way to bring Roe v. Wade back.

Which obviates the political point of the whole project. Anger at the current conservative majority and a desire to undo its decisions are what motivates this push for “reform” — watch for that loaded word in the coverage, by the way — of the Supreme Court.

There is no politically achievable way for progressive foes of this court to get what they want in the near or medium runs. Expanding the court to get new justices would be unpopular, and Democrats are not united on it. The courts would rightly swat down statutory term limits on existing justices. Term limits on future justices would take enormous political effort and offer progressives no payoff.

Biden and Harris are trifling with the Constitution. Even on the most charitable view, they are trying to rev up progressive enthusiasm for the Democrats by pretending to do something meaningful against the conservative justices. A generation ago, Sen. Daniel Patrick Moynihan (D-N.Y.) said his fellow Democrats were offering “boob bait for bubbas” to win conservative votes without delivering on the substance. This time, they’re selling boob bait for Brooklyn.