The main problem with "court packing" is that it won't work.

If Democrats were to succeed in adding members to the Supreme Court in order to tilt its ideological balance to liberals, Republicans will just tilt it back the next time they (inevitably) regain power by appointing even more conservative justices. Any new precedents created by a left-leaning court would be reversed the next time conservatives added seats. The ensuing battles would probably drain the high court of the support and respect it still commands from the American public.

There are few long-term victories for Democrats to gain from such a project, in other words, and plenty of pitfalls.

Yet packing the court remains popular, even imperative, among the party's activist base. That is why President Biden last week created a commission that will examine reforms both to the Supreme Court and the broader federal judiciary. (The commission will examine "the membership and size" of the high court.) Given Biden's well-known skepticism of court packing, the commission's birth might be a maneuver to keep his party's base at bay for the moment — but it could also be the first step toward big changes to the court.

Those changes would be welcomed by progressives who blame Republicans for creating a crisis on the court.

E.J. Dionne, a Washington Post columnist, recently summed up the pro-packing case this way: "The Supreme Court faces a legitimacy crisis not because progressives are complaining but because of what they are complaining about: a reckless, right-wing, anti-democratic court majority, and a conservative court-packing campaign marked by the disgraceful Republican blockade against President Barack Obama's nomination of Merrick Garland in 2016 and the unseemly rush to confirm Justice Amy Coney Barrett just before President Donald Trump's defeat last November."

This leads to the second, more imminent problem with court packing: It's not clear that American voters share Democrats' sense of grievance.

Though a commonplace notion among progressives, it might be wise to be skeptical of any proclamations that the court has lost legitimacy. Gallup polling over the last 20 years shows the Supreme Court's popularity has ebbed and flowed — but generally, more Americans have approved than disapproved of the job justices are doing. Another poll indicated that Republican support for the court dropped drastically in December, when justices refused to take up Texas' lawsuit challenging Joe Biden's presidential victory. Even then, in the wake of Barrett's confirmation, 43 percent of Americans approved of the Supreme Court's performance — while just 35 percent disapproved. That admittedly is not the widest of margins, but it's not all that bad in our era of political polarization. In most polls, the Supreme Court is usually more popular than the White House or Congress.

The public, it seems, is not crying out for reform.

Nor is the Democratic Party in lockstep agreement. In addition to Biden's caution on the issue, Sen. Joe Manchin (D-W.Va.) has declared himself against court packing — which means Senate approval in the 50-50 chamber would be tough to achieve. (And don't forget that Republicans would certainly filibuster any bill adding seats to the court.) Even Justice Stephen Breyer, one of the court's last remaining liberal justices, last week announced his opposition to the idea.

"If the public sees judges as 'politicians in robes,' its confidence in the courts, and in the rule of law itself, can only diminish, diminishing the court's power, including its power to act as a 'check' on the other branches," Breyer said in a speech at Harvard Law School.

If packing advocates overstate the court's legitimacy crisis, Breyer probably underplays how much the court is already seen as a political institution. The Supreme Court doesn't always deliver on partisan goals; Trump might still be president if that were the case. But the fierce confirmation battles of recent decades, pitting Republicans against Democrats in ever-more-heated clashes, have given the public ample reason to believe that politics do permeate its business. Still, Americans and their elected officials continue to obey the court's rulings and adhere to its precedents. That's the ultimate form of legitimacy.

None of this is to say that progressives should be satisfied with the court's rightward turn. For the moment, however, there may not be much that can be done about it. Democrats need to convince the public — and more of their own elected officials — that big changes are needed. Unless that happens, court packing is just a pipe dream.