Members of the US Senate sit down to a bipartisan caucus in the Old Senate Chamber at the US Capitol in Washington, January 4, 2007. (Reuters/Jonathan Ernst)

If Congress during the Obama era is marked by one thing, it’s partisan gridlock: a constant parade of crisis showdowns, filibusters, and partisan votes—like when every Republican in the House and all but three in the Senate voted against the stimulus package one month into Obama’s term.

So what happened Wednesday night in the House—and why it happened—is worth thinking about for a while before the news machine zooms past.

Representatives Justin Amash and John Conyers created an amendment to a big defense appropriations bill, which used targeted language to defund the bulk collection of data by the National Security Agency. This was the practice disclosed by Edward Snowden and The Guardian in early June. Amash managed to get the amendment to the House floor.

Politico suggests House leadership allowed a vote because they were sure it couldn’t pass—though that seems like a contestable assumption. The administration seemed quite worried that it would: NSA director Keith Alexander was immediately dispatched to the Hill to lobby members against the amendment.

The White House also released a veto threat on the same day, a somewhat unusual move for a single amendment that supposedly had no chance of passing. The White House declared, “This blunt approach is not the product of an informed, open, or deliberative process.”

The debate on the House floor late Wednesday, however, was remarkable for how open and deliberative it was: except a couple September 11 references and warnings of “Islamic jihad,” the debate was respectful, well-informed and broadcast on C-SPAN as much of official Washington watched, transfixed.

It was also remarkable for the unusual bipartisanship—hardcore Tea Partiers stood up with old-school urban liberals and railed against the NSA program, while high-ranking Democrats and people like Representative Michele Bachmann took the other side.

The final vote was just as amazing:

This was one of the most bipartisan votes on a matter of significance in the Obama era—on a day when only hours earlier, the president was in Illinois, railing against congressional gridlock. (It may be the most bipartisan vote since 2009 that didn’t have to do with a post office or other routine matter—I’m open to hearing counter-examples in the comments.)

Somewhat incredibly, this happened despite the urgent pleas of party leaders. A majority of Democrats—and not a narrow majority—voted against not only warnings from the Democratic White House but also House minority leader Nancy Pelosi and her leadership team, which was whipping against the vote.

And all this happened in response to what is truly an unprecedented expansion of the surveillance state. Snowden’s disclosures about mass NSA spying did what virtually nothing else could since 2009: unite Republicans and Democrats in Congress.

This has serious implications for whether the rapidly expanding domestic surveillance apparatus can be checked. Recall that earlier this week Senator Ron Wyden warned that if action didn’t happen now, the country risked entrenching a surveillance state that “cannot be reversed.”

Wednesday’s vote augurs well for such a check. In a House Judiciary hearing last week, Representative James Sensenbrenner said plainly, “There are not the votes in the House of Representatives to renew Section 215,” which is the provision in the Patriot Act that allows a good deal of the bulk collection conducted by the NSA. That now seems like a reasonable prediction.

At the very least, one can assume there’s broad support for some of the more moderate measures to combat the secrecy surrounding domestic surveillance—bills have been introduced that would mandate disclosure of FISC opinions, add a civil liberties advocate to the secret court, change how those judges are appointed, and other steps.

That is something everyone should pay attention to—you can bet the administration and national security officials sure are.

For more, Chris Hayes and David Sirota discussed this re-shuffling of the partisan deck on All In last night:

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