Senate Republicans took the "nuclear option," to break the filibuster on Supreme Court nominee Neil Gorsuch on April 6, and both parties pointed fingers at the other for the divisive rules change. (Jenny Starrs/The Washington Post)

The Senate just went “nuclear.” After Democrats successfully filibustered Neil Gorsuch's Supreme Court nomination Thursday morning, Republicans simply reduced the threshold for Supreme Court picks from 60 votes to a majority — very likely changing the Senate forever.

Republicans cite Democrats' 2013 move to nuke the filibuster for non-Supreme Court nominees to justify their actions, and Democrats cite the GOP's obstruction of Merrick Garland last year to justify their highly unusual filibuster. Both have extremely valid points.

But the truth is that it's all a rather predictable result. And the causes aren't just the things we often cite, like polarization, gerrymandering or fateful maneuvers by our leaders; it's also about our increasing political nihilism.

In announcing his clearly reluctant decision to support the filibuster this week, former Senate Judiciary Committee chairman Patrick J. Leahy (D-Vt.) conceded that the Senate he had served in for four decades had simply changed. “I cannot vote solely to protect an institution,” he said. “I fear that the Senate I would be defending no longer exists.”

Sen. Leahy (D-Vt.) delivered a strong rebuke of the changing partisanship in the Senate on April 3. "I fear that the Senate I would be defending no longer exists," he said of the impending GOP decision to change filibuster rules over Judge Gorsuch's Supreme Court nomination. "I will not, I cannot support advancing this nomination." (Reuters)

Sen. John McCain (R-Ariz.), meanwhile, said anyone who thinks the nuclear option is a good thing is “a stupid idiot” — two days before he voted to go nuclear.

Both of these senators and plenty of others projected profound reluctance about the steps they were embarking upon, but they still went through with it of their own volition. They hadn't changed, they insisted, but the other side had forced their hands. The Senate just wasn't what it once was.

More realistically, though, it's our politics that aren't what they once were. Fewer and fewer things are sacred, and political norms are being cast aside in the name of base politics with an alarming frequency. President Trump certainly cast a spotlight upon this trend — and exploited it — but it was already happening.

Democrats probably wouldn't have filibustered Gorsuch if not for the immense pressure they received from their base. There were multiple times when a Democratic senator sounded as though he or she didn't want to filibuster — Leahy and Sen. Jeanne Shaheen (D-N.H.), specifically — and were forced to quickly clarify that their stances were in line with the base.

So they launched what was basically an unprecedented filibuster. No, the filibuster wasn't completely unprecedented — as The Fix's own Amber Phillips reported, a mostly partisan filibuster blocked Abe Fortas's nomination to be chief justice a half-century ago — but it was completely unusual in that Gorsuch didn't seem to have any disqualifying attributes, and it wasn't a lame-duck president's nominee. And in doing so, Democrats repeatedly and misleadingly evangelized the 60-vote standard.

Going back to 2013, Democrats only invoked their nuclear option after Republicans spent the better part of the Obama presidency wielding the filibuster with unprecedented frequency against his nominees. Republicans often argued that President Barack Obama's liberalism was unprecedented, so it must be met with such unprecedented obstructionism.

And last year, Republicans wouldn't even allow Obama's nomination of Garland a hearing, justifying this by citing a so-called “Biden Rule” that wasn't really that analogous. It was a nakedly partisan ploy, and it worked. Democrats tried hard to make it an issue in the 2016 election but quickly gave up.

The common link between all of these is that each step was outwardly justifiable to the party that was taking it, and that justification was good enough for partisans — even if it didn't hold water, strictly speaking. It was a gray area that politicians gladly exploited — and that their bases, in fact, demanded they exploit. In none of these cases did breaking with political norms alienate anyone in the party's increasingly loyal bases, and in none of them did the gambit seem to have an appreciable effect on the political middle.

Against that backdrop and going forward, it's not difficult to see how the two parties believe they can justify any nakedly political moves. And the unraveling of these traditions is a slippery slope, in which both parties just assume the other side will probably take the next step when they're in power, so why wait?

The only things standing in their way now are tradition and a sense of the collective good. And tradition doesn't seem to count for much anymore.