In one of the most striking exchanges on the Senate floor in recent memory, Majority Leader Harry Reid and Minority Leader Mitch McConnell sparred for over an hour on arcane rules, as the normally-collegial body debated the Chinese currency bill.

Technically at issue were nine amendments offered on the bill, two of which Senate Democrats were unwilling to vote on — including the original version of President Barack Obama's jobs bill that McConnell wanted to vote on knowing it would fail.

But the argument was about much more than the jobs bill or currency manipulation — it was about the very culture of the nation's greatest deliberative body.

After cloture was reached on the currency bill, McConnell called for multiple procedural "motions to suspend the rules," which would have forced embarrassing votes on the issues — a tactic used occasionally to make a political point on controversial legislation.

In response, a frustrated Reid invoked the rarely-used "tactical nuclear option" to change the Senate rules by a simple-majority vote to make it impossible for the minority party to call for such votes. He justified it saying it would allow un-ending motions and votes — serving as a second filibuster after the Senate has already voted to end debate.

“If I were in the minority, I wouldn’t do this, I think it’s dilatory and wrong,” he said.

“The Republican Senators have filed nine motions to suspend the rules to consider further amendments but the same logic that allows for nine such motions could lead to the consideration of 99 such amendments,” Reid said before moving to change the rules.

“This has to come to an end. This is not a way to legislate,” Reid said, warning of an “endless vote-a-rama,” without the change.

Reid's move is different than the so-called 'nuclear option' — which was considered during the health care reform debate and as a way to clear a backlog of judicial appointments. Such a measure would rewrite Senate rules to eliminate the filibuster entirely.

McConnell was irate at the rules change, which sets a precedent for the majority party to amend the rules to block opposition motions — and may come back to bite Democrats if they lose the majority.

“Look, let’s don’t change this place,” McConnell said in an impassioned speech. “America doesn’t need less debate. It needs more debate...I think we made a big mistake tonight. And as soon as we all kind of cool off and think about it over the weekend, I hope we’ll undo what we did tonight because it’s not in the best interest of this institution or the American people.”

The Senate will vote on the final currency bill — without the amendments — on Tuesday, but the damage to the chamber's ability to legislate may already be done. Traditionally the "saucer" that cooled the fiery whims of the House, the Senate is now little better than its counterpart.

Watch the shocking exchange at C-SPAN >