“No majority leader wants written on his tombstone that he presided over the end of the Senate,” the minority leader said.

He continued: “Breaking the rules to change the rules is un-American. I just hope the majority leader thinks about his legacy, the future of his party, and, most importantly, the future of our country before he acts.”

Are these the words of Minority Leader Chuck Schumer (D-N.Y.) as the Republican majority changed Senate rules this week to do away with filibusters of Supreme Court nominations?

Actually, they were uttered in 2013, by then-Minority Leader Mitch McConnell (R-Ky.), when Democrats pushed through a similar filibuster change for lesser nominations.

That McConnell did a 180 on the topic — going from the institutional defender of the filibuster to the man who destroyed it — is unsurprising. He has frequently shifted his views to suit the needs of the moment. But in this case McConnell was correct in 2013, and what he just did this week was even more ruinous than what he accused the Democrats of doing then.

By rights, McConnell’s tombstone should say that he presided over the end of the Senate. And I’d add a second line: “He broke America.” No man has done more in recent years to undermine the functioning of U.S. government. His has been the epitome of unprincipled leadership, the triumph of tactics in service of short-term power.

After McConnell justified his filibuster-ending “nuclear option” by saying it would be beneficial for the Senate, Sen. John McCain (R-Ariz.) said this: “Whoever says that is a stupid idiot.”

McConnell is no idiot. He is a clever man who does what works for him in the moment, consequences be damned.

Back in 1994, McConnell lamented to the conservative Heritage Foundation that Republicans hadn’t used the filibuster enough: “I am a proud guardian of gridlock. I think gridlock is making a big comeback in the country.”

For the next quarter-century, he made sure of it. Back then he was fighting all attempts at campaign-finance reform and spending limits, championing disclosure of contributions as the antidote. But when the Supreme Court allowed unlimited “dark money” in campaigns without disclosure, McConnell reversed course and has fought all attempts to enact disclosure.

McConnell famously declared in 2010: “The single most important thing we want to achieve is for President Obama to be a one-term president.”

ProPublica’s Alec MacGillis, author of a McConnell biography, “The Cynic,” reports former Republican senator Robert Bennett’s account of what McConnell told fellow Republicans after Obama’s election: “Mitch said, ‘We have a new president with an approval rating in the 70 percent area. We do not take him on frontally. We find issues where we can win, and we begin to take him down, one issue at a time. We create an inventory of losses, so it’s Obama lost on this, Obama lost on that.’ ”

And that’s what he did. By 2013, for example, 79 of Obama’s nominees had been blocked by filibusters, compared with 68 in the entire previous history of the Republic.

After Justice Antonin Scalia’s death was confirmed last year, it took McConnell less than an hour to say that the vacancy should be filled by the next president. He called keeping Obama’s nominee off the court “one of my proudest moments.”

While other Republicans have at times been willing to criticize President Trump’s outrages, McConnell has been conspicuously quiescent. Although his predecessors at least attempted collegiality, McConnell practices no such niceties (recall his “nevertheless, she persisted” silencing of Massachusetts Democratic Sen. Elizabeth Warren). But most characteristic of McConnell is his tendency to shift his views to suit current exigencies (on the minimum wage, withdrawal from Iraq, earmarks, abortion, labor and civil rights) and his adroitness at gumming up the works: forcing clerks to spend hours reading a bill aloud on the floor; opposing immigration legislation he’d encouraged; asking for a vote on a debt-ceiling proposal and then trying to filibuster it; urging the Obama administration to support a bipartisan debt commission and then voting against it.

Now comes the filibuster’s demise. In the current cycle of partisan escalation, it’s only a matter of time before the filibuster is abolished for all legislation, killing the tradition of unlimited debate in the Senate dating back to 1789. The Founders did this so minority rights would be respected and consensus could be formed — and McConnell is undoing it.

Two years ago, when a Democrat was in the White House, McConnell said he would only abolish filibusters of Supreme Court justices if there were 67 votes for such a change. This week, he employed a maneuver to do it with 51 votes. It suited his momentary needs, but the damage will remain long after McConnell’s tombstone is engraved.

Twitter: @Milbank

Read more from Dana Milbank’s archive, follow him on Twitter or subscribe to his updates on Facebook.