Until yesterday, Joe Bidens agenda was stalled in the Senate by a primal conflict over power.

The context was negotiations over how the two parties would navigate their 50-50 split. While, as majority leader, Chuck Schumer would control the legislative calendar, he offered to divide committee membership equally under Democratic chairsreplicating the arrangement in 2001 when there was an evenly divided Senate with a Republican vice president. Incredibly, the newly demoted Mitch McConnell responded by demanding that Democrats agree not to abolish the filibuster.

The requirement of a 60-vote supermajority had enabled McConnell to stonewall Barack Obamas legislative agenda. Yet he blithely repackaged it as a lubricant for bipartisanship while striving to re-empower his party, once more, with a legislative stranglehold on another Democratic presidenteffectively requesting that Schumer and his caucus become senatorial castrati.

Unsurprisingly, Schumer declined. Knowing that Schumer could use an arcane maneuver to pass the organizing resolution by a bare majority, McConnell ultimately yielded. But by then he had achieved his goal: moving moderate Democrats from red statesJoe Manchin, Kyrsten Sinema, and Jon Testerto expressly oppose abolishing the filibuster, underscoring the partys divisions and the vulnerability of Bidens agenda.

The unanimous support of Schumers caucus is the mathematical prerequisite for changing the Senates rules and, therefore, abolition. Still, he at least retained the threat should the GOP prove obstructive, and the moderates backed his refusal to cave.

This suggests the possibility, however dim, that scorched-earth opposition could affect their thinkingespecially if it scotches proposals popular with crucial constituencies. As Tester told the New York Times: If all that happens is filibuster after filibuster, roadblock after roadblock, then my opinion may change. This augurs the three-dimensional chess ahead, and the prospects of two different Biden presidencies: consequential or ineffectual.

To be sure, Biden can enact much of his COVID-19 stimulus package through budget reconciliation, a means of passing fiscal measures with a simple majority. But reconciliation has real limitations: It does not apply to most legislation, and on spending measures can be used only once a year. Moreover, turning Bidens stimulus plan into a meaningful package with majority support will prove more than challenging enough.

Beyond that, the GOP can use the filibuster to block major Democratic initiatives. Heres a representative sample: a $15 an hour minimum wage; comprehensive immigration reform; repairing the Voting Rights Act; strengthening the right to join a union; granting statehood to Washington, D.C. and, perhaps, Puerto Rico; enacting ethics and campaign finance reform; curbing gerrymanders; and passing initiatives to combat racial inequities in law enforcement.

Among most Democrats, particularly progressives, these proposals are popular. But query whether their death by filibuster would move red-state moderates to sign on for abolition. It seems equally likely that the artful threat of filibusters could divide the Democratic caucusnot just over the filibuster itself but over what legislative compromises with Republicans, if any, are acceptable.

This prescription could doom much of Bidens agenda, and make McConnell the most powerful minority leader in memory. To reinforce his leverage, yesterday McConnell threatened that Democratic efforts to eliminate the filibuster would destroy any hope of comity and create a legislative wasteland:

But suppose that Republican obstreperousness created a critical mass among Democrats. If they could abolish the filibuster, should they?

As Jonathan V. Last spelled out on Mondayits complicated.

First, the equities. Even without the filibuster, the structure of the Senate itself frustrates popular democracy by giving each state two votes. Due to demographic sorting, the 50 Republican senators represent nearly 42 million fewer people than the 50 Democrats; the 41 Republicans necessary to sustain a filibuster reflect a relative fraction of our populace.

This is a prescription for quashing popular legislation and imposing legislative stasisMcConnells specialty. Given that restructuring the Senate would require a constitutional amendment supported by the very states it overrepresents, the only way of making the Senate less undemocratic is eliminating the filibuster. Those who laud the filibuster as a safeguard against the tyranny of the majority enshrine the tyranny of a minority.

So why should Democrats keep it? First, because legislation which survives the filibuster is more apt to endure. Second, given the advantages which may create a Republican majority two years hence, Democrats could constrain it through the filibuster.

But consider history and human nature. When Democrats tried to filibuster Neil Gorsuch, McConnell and his caucus simply killed the filibuster for Supreme Court nominees. Can anyone seriously argue that McConnell wouldnt once again invoke this nuclear option whenever it suited him?

Moreover, during Trumps presidency Senate Democrats could not use the filibuster to frustrate the GOPs major goals. Republicans tax cuts passed through reconciliation; the slew of judges they confirmed were no longer subject to the filibuster. Given the GOPs general lack of enthusiasm for governance, the filibuster affects them less than Democrats.

In this moment, there is an urgent need for Joe Biden to reinvigorate democracy by making government work for the greater good. If the Democrats dont succeedor at least do their damnedestwhere would that leave us? In the hands of a party which will do its worstor nothingperhaps despoiling Americas last, best chance to do better.

If Democrats garner the votes to kill the filibuster, they should.

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Can Democrats Abolish the Filibusterand Should They? - The Bulwark