This article is from the archive of our partner .

It was a precedent-setting night in the Senate Thursday evening and both liberals and conservatives are troubled by what may come of it. In a standoff between Republicans and Democrats, Senate Majority Leader Harry Reid overhauled a key Senate rule that may fundamentally diminish the powers of the minority party in the Senate. It was a confrontation that began by Republicans trying to make Democrats look bad but ended in a way nobody predicted.

In the run-up to the standoff, Republican Minority Leader Mitch McConnell moved to force a vote on the American Jobs Act, knowing that some Democrats facing reelection would vote it down, demonstrating bipartisan opposition to President Obama's jobs package. But Reid blocked McConnell's motion. "Reid argued that [forcing a vote] amounted to another filibuster, because it required 60 votes to move back to the original bill, and so therefore was out of order," explains The Huffington Post's Ryan Grim and Michael McAuliff. "Sen. Mark Begich (D-Alaska), who happened to be the presiding officer at the time, asked the Senate parliamentarian what he thought. The parliamentarian advised Begich that McConnell's motion was in order," they write. "Reid then appealed the ruling, following a script that advocates of ending the filibuster wrote long ago. What some senators call the 'constitutional option,' and what others call the 'nuclear option.'" And that has people up and down the political spectrum worried.

Why it matters Karoun Demirjian at The Las Vegas Sun explains:

From this night on, senators will no longer be able to move to suspend the rules that require all bill amendments to be on-topic, a move the minority party sometimes avails itself of to force votes on topics the majority would rather block. It's known as the "nuclear option," but just as with real nukes, the bomb is rarely dropped in battle.

Why the right's angry First off, it foiled their plans to make Democrats look divided. Secondly, it blocks their power as a minority force in the Senate. “We are fundamentally turning the Senate into the House,” McConnell said on the Senate floor.  “The rules of the Senate will be effectively changed to lock out the minority party even more.”

Why the left is worried As Brian Beutler at Talking Points Memo explains, this may very soon come to haunt Democrats:

Reid has wiped out an extremely small minority right (technically, the right to force a vote on a motion to suspend the rules after cloture has been invoked on a bill to consider a non-germane amendment). But he's done so at the nadir of Democratic power with Republicans strongly positioned to assume the majority in 2012. Republicans are furious about it. And now that Reid's done something that hasn't been done in at least 30 years -- and may be unprecedented -- a narrow GOP majority in 2013 could use it as cover to affect much broader changes to the Senate rules. Including, if they want, eliminating the filibuster.

If Republicans win the Senate in 2012, we all may be revisiting this odd procedural maneuver, but with much, much more at stake.

On the other hand, some Democrats shrugged off those concerns, telling Politico that "efforts to waive the rules are similar to the stall tactics Republicans have employed time and again. A motion to suspend the rules has not succeeded since 1941 ... meaning that such efforts typically amount to political messaging more than anything else."

This article is from the archive of our partner The Wire.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.