Democrats are increasingly confident of pulling off a trifecta in November — defeating Donald Trump, winning a majority of the Senate, and remaining in charge of the House of Representatives. If it happens, Democrats would have unified control of the White House and both chambers of Congress for the first time since 2009. But it still wouldn’t give them unchallenged power to muscle through any piece of legislation the party supports — not as long as the Senate retains the legislative filibuster, which, under current rules, requires the support of at least 60 senators to bring a bill to a vote.

Consequently, pressure is growing within Democratic Senate ranks to abolish the filibuster if the party triumphs on Election Day. That would mean that the next Senate would need only a bare majority vote to pass everything on the progressive wish list, from the Green New Deal to statehood for the District of Columbia. During his 36 years in the Senate, Joe Biden always supported the filibuster as a key protection for the minority party against the tyranny of the majority party. But the presumptive Democratic nominee signaled last week that he will not object if his party moves to change the rules should it win a Senate majority in the fall.

In an interview with the New York Times, Biden was asked whether he supports doing away with the filibuster. “It’s going to depend on how obstreperous they become,” he said, referring to Republicans. “I think you’re going to just have to take a look at it.”

Wrangling over the filibuster isn’t new. The practice is not mandated by the constitution; it’s merely a creation of the Senate rules, and senators have debated for years the form it should take. Before 1917, debate in the Senate had no limit — as long as any senators were prepared to keep discussing a measure, it could be kept from a vote indefinitely. In 1917, prodded by President Wilson, the Senate adopted a rule modifying the filibuster: For the first time it authorized “cloture” — the closing of a debate — if two-thirds of the senators agreed. Decades later, the threshold needed to invoke cloture was lowered to 60, which is where it remains today, at least in theory.

But it’s not that simple.

The filibuster has on the whole been a good rule, one that restrains majorities of either party from riding roughshod over the minority. Under Mitch McConnell and the Republicans, no less than under Harry Reid and the Democrats, the filibuster has prevented the Senate from becoming merely a smaller version of the House of Representatives, where the minority party has no bargaining power at all, and debate is ruthlessly curtailed.

It is true, as some on the left have been fuming lately, that as long as it takes 60 votes to get a controversial bill passed, Democrats’ most radical proposals will never be enacted, even if Biden takes the White House and Chuck Schumer becomes majority leader. But that has been the reality on the right, too. Despite having a Republican president and Senate majority, the GOP has not been able to repeal Obamacare or deliver the border wall Trump craves: It has never been able to muster the necessary 60 votes. That explains why Trump has been as adamantly anti-filibuster as, say, Elizabeth Warren. “Republicans must get rid of the stupid Filibuster Rule — it is killing you!” he tweeted in 2018 in a typical denunciation. On that issue, if on no other, the president and the Massachusetts senator are in sync.

So should senators dump the filibuster?

No. They should restore it.

At their best, filibusters can be a valuable restraint on congressional overreach and runaway populism. Used prudently, a filibuster shelters the minority’s right to be heard and pumps the brakes on surging legislative enthusiasm. The problem with the filibuster isn’t that it exists, but that its use has become both routine and invisible. How this paradox came to be is a classic tale of unintended consequences, which I recounted in a column last year:

It used to be that any senator or group of senators could indefinitely block a vote on a bill the way Jimmy Stewart did in “Mr. Smith Goes to Washington” — by taking the floor to speak and refusing to stop until the majority agreed to give ground (or exhaustion overtook the speaker). Critically, while a filibuster was underway, all other Senate business was suspended.

But in 1970, then-Majority Leader Mike Mansfield introduced a “two-track” system, under which a bill being filibustered would be set aside so the Senate could take up other matters. The result was not what Mansfield doubtless expected — making filibusters less desirable by stripping them of their power to gridlock the Senate. Instead, the number of filibusters soared. Or rather, the number of threatened filibusters soared. Those threats never had to be made good. The mere announcement that Senator X intended to filibuster Bill Y created a de facto requirement for a supermajority to move the legislation forward. Soon it was taken for granted that nearly every bill needed 60 votes to pass.

The solution to this problem isn’t to eliminate filibusters altogether, but to eliminate the two-track system that has made them ubiquitous. Senators were far less likely to undertake a filibuster back when they knew that doing so would bring the Senate to a halt. It was a weapon used sparingly. During the entire 19th century there were only 23 filibusters. Since 1970 there have been more than 1,000.

The Senate can make filibusters rare again by making them real again. A determined minority should have the ability to resist passage of a measure they find intolerable. But they should also have to demonstrate their resistance the hard way — by taking the floor, staying on their feet, speaking without letup, and facing the consequences. Then and only then should it require a supermajority to cut off debate and vote.

All the talk of whether Democrats should eliminate the filibuster if they take control of the Senate is missing the point. The filibuster was eliminated decades ago, and it was replaced with something more like a genteel blackball — a mere agreement-by-courtesy not to take up a bill. Mansfield’s innovation hasn’t served anyone well, and it’s long past time to undo it. Senators who wish to block a piece of legislation from coming to a vote should be required to fight it on the floor of the Senate. If they aren’t willing to do that, then they have no right to complain when it passes with a simple majority.

Democrats and Republicans, debating whether to get rid of the filibuster, are on the wrong track. What they should really be debating is how to get it back.

(Jeff Jacoby is a columnist for The Boston Globe).