A filibuster permits a senator to stop popular legislation. Initially, it required a senator to hold the floor by refusing to stop talking, which took many, many hours and was exhausting, so it was a last resort to stop something that otherwise would pass (and was almost always used to stop civil rights legislation). But, rules changes over time changed the filibuster to permit a senator to stop legislation simply by threatening to create such a roadblock.
This has meant that the burden of passing legislation has fallen on the majority, which needs to find 60 votes to stop a filibuster rather than a simple majority of 51 to pass a bill, while the role of the minority has simply been to refuse to entertain action. The Senate has largely ceased to legislate. This development has served the Republicans, who are happy not to pass legislation because they would like to turn the functions of government over to private interests, but frustrates the Democrats, who think that bills that pass the House of Representatives should get a hearing in the Senate and, if they get a yes vote from a majority of senators, should pass.
There has been resistance to ending the filibuster—including resistance from President Joe Biden—but there is increasing talk of returning the filibuster to its original form, requiring those opposed to a popular measure not simply to register their disapproval in order to take it off the calendar, but actually to hold the floor to talk a measure to death. When they give up, the measure can pass by a simple majority vote.
At stake in this issue in the immediate future is the passage of H.R. 1, the For the People Act, a sweeping voting rights bill passed last week by the House of Representatives. Senate Republicans have vowed to kill the bill. Increasingly unpopular, Republicans are dependent on voter suppression techniques and gerrymandering—both addressed in the bill-- to continue to have a shot at winning elections. In illustration of that need, Republican legislatures across the country are currently trying to pass a slew of voter suppression measures.
For their part, Democrats recognize that if the Republicans’ voter suppression and gerrymandering techniques are allowed to go forward unchallenged, Democrats will be hard pressed ever again to win control of the government. The nation will, in effect, become a one-party state not unlike the one that controlled the American South from the 1870s to the 1960s.
So H.R. 1 spells the future of the American political system: with it, Republicans will have to reform and win elections on a level playing field; without it, Democrats will be unlikely to be able to compete against Republican rigging of the system.
The future of the nation depends on H.R. 1; the future of H.R. 1 depends on the filibuster.