I love the graph, but I didn't think this was a particularly good article. What's odd is that the Wonkblog email I got had a really great writeup, different, from the same source. I don't know. Here it is:

Fifty years ago today, President John F. Kennedy was gunned down in Dallas, Texas. But a bit over 52 years ago today, Kennedy changed American politics forever.

When Kennedy entered office, the Senate wasn't the only chamber where a small minority could block the large majority. It could happen in the House, too. The House Rules Committee, which was controlled by arch-segregrationist Howard Smith, could simply refuse to pass a rule on a bill. That kept the bill from going to the floor. It rendered the House a graveyard for civil rights legislation.

One of the most consequential moments in JFK's presidency came when he decided to spend political capital on one of those "process issues" that presidents typically ignore. He partnered with Vice President Lyndon Johnson and Speaker Sam Rayburn to expand the Rules Committee's membership. The battle, a clear proxy for the large civil-rights struggle, was vicious. Rayburn later called it "the worst fight of my life." But it was successful. The Rules Committee was expanded. That expansion made the Civil Rights Act of 1965 -- and much else that passed as part of the Great Society -- possible.

Kennedy's rules change is largely forgotten today. It wasn't even very well known in Kennedy's time. But it changed the face of America. Rules changes often do.

On Thursday, Senate Majority Leader Harry Reid forced a rules change that might well prove to be of equal consequence. Technically, his reform of the filibuster is modest: It lifts the 60-vote threshold on all executive-branch nominations and judicial nominations, save for the Supreme Court.

In practice, it is sweeping: By changing the rules mid-session with 51 votes, Reid unwound the Senate's multi-decade transition from a chamber where majorities ruled into a chamber where only supermajorities could govern. The filibuster is effectively dead and the majority, to a degree that hasn't been true in years, is back in charge. (For more on this, see 9 reasons this will reshape American politics .)

Reid's decision had more than a whiff of hypocrisy about it. In 2005, when Republicans considered a similar change, Reid called it "breaking the rules to change the rules." Of course, Minority Leader Mitch McConnell's outraged reaction was no less hypocritical. Back in 2005, he said changing the rules with 51 votes was simply "what the majority in the Senate has often done -- use its constitutional authority under article I, section 5, to reform Senate procedure by a simple majority vote."

The truth is Reid didn't break any rules on Thursday. As McConnell correctly said in 2005, Senate procedure can be reformed by a simple majority vote. What Reid did, rather, was break a norm against making major rules changes with 51 votes. And he didn't do it thoughtlessly. Reid is a fervent Senate institutionalist who has spent years blocking both Democrats and Republicans from changing the filibuster. But he's concluded that the only way to save the Senate is to begin rolling back the radical, revolutionary changes that have been made to it in recent decades.

There was no filibuster at the dawn of the Republican. The practice emerged only by accident : An overhaul of the Senate rulebook deleted a seemingly redundant motion. Decades later, the Senate realized they'd deleted the only rule that could end debate. But it wasn't a very big deal. Senators did not, as a matter of course, try to gum up the workings of the institution by talking endlessly from the floor. The filibusters that happened were rare, and it wasn't until 1917 that the Senate decided it needed any way to shut them off at all -- and even then, you needed 67 votes.

The Senate protected itself much more through norms than rules. The filibuster could've been used to plunge the entire chamber into organized dysfunction. But it just wasn't done.

And then something went wrong:

(graph)

The modern Senate is a very different place than the Senate of yore. And many of those changes -- including the startling rise of the filibuster -- can be traced to a single cause: Party polarization. Before the two parties became reasonably unified and disciplined ideological combatants, filibusters were rarely used as a tactic of inter-party warfare. The parties were too diverse for that: each political party had some members who supported and opposed the bills in question, and so they had no ability to organize a filibuster.

In the mid-20th Century, filibusters were mainly used by the Southern bloc to stop anti-lynching and civil rights bills -- but the Southerners knew that if they overused the filibuster, it would be eliminated. So filibusters were seldom seen on non-civil rights issues.

It was only as the parties polarized and began working against each other in a more organized fashion that the filibuster became a constant presence in the minority's efforts to undermine the majority. That change in norms meant a profound change in the Senate: It turned the chamber from a body where majorities ruled into a body where only supermajorities could rule.

As Gregory Koger, a University of Miami political scientist who researches the filibuster, told me: "Over the last 50 years, we have added a new veto point in American politics. It used to be the House, the Senate and the president, and now it's the House, the president, the Senate majority and the Senate minority. Now you need to get past four veto points to pass legislation. That's a huge change of constitutional priorities. But it's been done, almost unintentionally, through procedural strategies of party leaders." (Here's Koger on what happens next .)

The fundamental problem of today's Senate is that rules designed for cooperation are curdling in an era where polarization has made that cooperation impossible. On Thursday, Reid and the Democrats began rewriting the rulebook for a polarized age.

My colleague Dana Milbank laments the action as a "naked power grab," and he's right: It is a lamentable power grab. But so too was the rise in minority filibustering that led to it. It's lamentable power grabs all the way down. It would've been better if the rules could've been fixed collaboratively, but if that kind of cooperation was possible in today's Senate, then the fixes wouldn't be necessary in the first place.

That said, the Democrats didn't grab much power here. This change is happening in 2013, with a Republican House, not 2009, with a Democratic majority. The truth is there's a lot of upside for Republicans in how this went down.

It came at a time when Republicans control the House and are likely to do so for the duration of President Obama's second term, so the weakening of the filibuster will have no effect on the legislation Democrats can pass. The electoral map, the demographics of midterm elections, and the political problems bedeviling Democrats make it very likely that Mitch McConnell will be majority leader come 2015 and then he will be able to take advantage of a weakened filibuster. And, finally, if and when Republicans recapture the White House and decide to do away with the filibuster altogether, Democrats won't have much of an argument when they try to stop them.

So the question here isn't so much about the change in power now as it is in the change in power over time. That change doesn't clearly favor Democrats or Republicans. Rather, it favors majorities over minorities. And a corrective on that front has been overdue for decades. The only thing worse than a Senate where the majority has the power to govern is one where it doesn't.