The Senate majority leader and 51 other Democrats voted today to change the chamber’s rules—departing from over 200 years of tradition—to make a 51-vote majority sufficient to confirm most presidential nominees, though notably not those for the Supreme Court. It’s arguably the biggest change to the institutional character of the Senate since the ratification of the 17th amendment. Consensus-seeking collegiality had already broken down, but now the formal incentive to seek it is gone. That incentive, it need hardly be said, hadn’t proved very effective lately.

In theory you might now get more intensely partisan nominees and greater polarization of the federal bench, as well as cabinets that are even less aware of the need to build more-than-majority-support for policies that affect everyone. American government has generally not been a thing of bare majorities, which tend to be unstable, and the political problems of Obamacare—quite apart from its policy and technological ones—are a product of a short-lived Democratic majority trying to make a great change without securing even grudging support from the other side. This all-at-once approach cost the Democrats their House majority in the following election and set the stage for years of acrimony.

Other changes in the way the Congress operates, under Republicans and well as Democrats, have similarly chipped away at the consensual—or at least supermajoritarian—character of the federal government: without earmarks and the old committee system, the wheeling and dealing that could be used to build consensus across party lines has been made much more difficult. Even earlier, reforms to the appropriations process in 1974 paved the way for Congress to become an “incompetent bureaucracy,” as this Bruce Bartlett piece explains, unable to pass budgets in anything like a reliable manner.

Reid’s change to the filibuster rules, and the conditions that prompted it, are another chapter in a decades-long tale of institutional decay. The book still has many pages to go, but one can guess how it ends. In 1776 Americans were so passionate about the idea of representative government that they were willing to fight a revolution for it. Nowadays Congress is lucky if its approval ratings hover just above the single-digit range.