The Senate’s filibuster rule appears nowhere in the US Constitution, but if it continues to be exercised in its current form, it will kill any hopes for the progressive agenda and reinforce the most destructive tendencies of the Republican Party. Under current Senate rules, it takes a supermajority of 60 votes for lawmakers to build something, but only 50 for them to tear it down. This baseline asymmetry allows the GOP to continue dismantling the government and leaves the Democratic Party unable to pass the bold plans necessary to build a progressive future.

The core Republican agenda has three crucial elements. The first is cutting taxes for the rich, because the GOP insists that low taxes drive growth and that progressive taxation unfairly punishes society’s winners. The second is disassembling the social safety net via privatization, vouchers, or block grants and starving the rest of the federal government of funds (except for the military). Republicans do this because they’re convinced that church groups and local communities can provide social insurance better than the federal government—an idea that was already anachronistic when it was tried during the Great Depression. The third is using the judiciary to tie reform efforts into knots, weakening or killing any regulations.

None of this requires a 60-vote supermajority in the Senate. A process called “reconciliation” allows budgeting and tax measures to pass with only 50 votes (and the vice president casting a tiebreaker). To choke off government services, Republicans simply need to constrict or redirect the budgeting and tax stream—and they’ve been ruthless at this. They have repeatedly passed 10-year tax cuts for the rich, forming new baselines for what voters expect to pay in taxes and creating political headaches for liberals when these cuts expire. The GOP has also invented elaborate ways to gut agencies like the Consumer Financial Protection Bureau through funding mechanisms, though they have yet to pass them.

The entire Republican debate on repealing the Affordable Care Act took place within this 50-vote threshold. Whether it was turning health care over to the states entirely, phasing out the ACA’s expansion of Medicaid, defunding Planned Parenthood, or enacting a last-minute “skinny repeal” of small, targeted cuts, the Senate needed just 50 votes to accomplish any (or all) of this. It was very different from the passage of the ACA, which required 60 votes.

Keep in mind that the last time the filibuster posed a real obstacle to the GOP’s agenda—when it was blocking Neil Gorsuch from taking a stolen Supreme Court seat—Senate majority leader Mitch McConnell simply repealed that part of the rule book. Meanwhile, with a conservative judiciary in place, the actions that Republicans would need 60 votes for, such as repealing the Voting Rights Act, don’t need to pass the Senate, since the Supreme Court has already eviscerated the Voting Rights Act for them.

Though various experts are now debating what could or could not move within this 50-vote threshold, it’s clear that the filibuster will distort and limit the scope of the progressive agenda—and on the same scale that Southern white supremacy limited the vision and scope of the original New Deal. A Green New Deal that unapologetically uses public power to curb carbon emissions and create an economy with better jobs for many would almost certainly require 60 votes; tinkering around the edges of the climate crisis with green subsidies and tax breaks for private businesses would need just 50. The same is true for any serious expansion of Medicare. Also, since the reconciliation process is tied to yearly budgets, it means fewer and bigger bills that are more vulnerable to collapse. Plus there’s a wide range of necessary reforms, from the $15 minimum wage to restoring voting rights, that can’t even be included under the Senate’s current rules on reconciliation.

To overhaul our carbon economy and address its many economic injustices, progressives must be able to pass ambitious legislation. In theory, the filibuster affects both parties, but in reality, it shackles the agenda of progressive Democrats while institutionalizing the Republican Party’s cruel nihilism.