Harry Reid (AP Photo/Manuel Balce Ceneta) Harry Reid (AP Photo/Manuel Balce Ceneta)

Harry Reid and the Democrats today have acted: we have majority-imposed rules change in the Senate, by a 52-48 vote. All Republicans opposed the change, and three Democrats — Joe Manchin, Mark Pryor, and Carl Levin — joined them. From now on, simple majorities will be sufficient to confirm executive branch and judicial nominees. Reid made an exception for Supreme Court nominees, but that’s surely a technicality; if and when a successful filibuster is conducted against a Supreme Court choice, it’s virtually certain that the exception will be closed.

This is a major, major, event. It changes how the nation is governed in a significant way. That said, it’s not as if the Senate has been static since the last time filibuster rules were changed (at least in a major way) almost 40 years ago; most reform is incremental, and one could argue that the rules change today returns nominations closer to how things were done in the 1970s than they have been for the last decade, and especially during the Obama era. However, what’s more likely is that we’ll see a Senate that isn’t really like either of those bodies.

This change was basically forced by Republicans; the interesting question, I think, is why the group of Republicans who weren’t willing to push the Democrats over the brink in the summer decided to do so now.

As far as the future, there are quite a few questions we really don’t know the answers to yet:

* Will the Republicans retaliate? How? The reason it’s called the “nuclear option” is because the minority has always threatened to “shut down” the Senate using other procedural tricks if it happened. I’ve been skeptical that they’ll follow through, but we’ll see.

* Outside of obstruction and retaliation, will going nuclear affect the ability of the parties to work together in areas, such as the budget, where they must make deals?

* What of the legislative filibuster? Now that majority-imposed reform has happened, will it spread rapidly to legislation the next time it matters? Or will the incentives for Senators to retain it — keeping their individual influence — preserve it?

* How will the new Senate actually work out in practice on nominations? Will Senators still be able to put holds on nominations when it isn’t backed up by the need for a super-majority to move to a final vote? It’s worth noting that the filibuster/cloture procedure was not eliminated (at least if I understand correctly); instead, the number for cloture was dropped to a majority. Therefore, an objection can still slow things down for several days. Of course, now that the precedent has been set, that could be eliminated as well, presumably.

We really don’t know exactly how this will play out, and what the Senate will be like in 2015. It’s going to be fascinating to watch. But it’s certainly a major, important change. And one thing that does appear clear: Barack Obama’s nominees will soon be sitting on the DC Circuit Court.