The Senate left town in frustration after once-promising talks on compromise over an extension to unemployment benefits collapsed. Harry Reid had managed to get six Republicans to vote for a debate over the bill, but when he locked Republicans out from being able to offer amendments, his fragile coalition fell apart:

But hopes for a breakthrough were dashed when Senate Majority Leader Harry Reid (D-Nev.) offered up a mostly Democratic-driven plan that would cover the $18 billion cost of extending the federal benefits through November.

Senate Republicans were further incensed when Reid told them he would not allow any amendments to the plan.

“I have been waiting here for more than 24 hours for a reasonable proposal by my Republican friends to pay for this. We don’t have one yet,” Reid said on the floor.

Republicans lashed out at Reid, arguing that they had put ideas forward and that all they wanted to do was sit down and work out a bipartisan agreement.

The move came at an odd time, since Democrats have demanded action from the GOP on an extension to these benefits, which expired in December. When enough Republicans voted to allow debate, the opportunity to pass an extension seemed at hand, which would have given Democrats some credit for driving to a solution.  Instead, Reid pulled a stunt that has become the norm during his tenure as Senate Majority Leader, called “filling the amendment tree,” which leave Republicans no opportunity to offer any changes for a vote.

Needless to say, GOP leadership and rank and file called foul:

What was shaping up to be a humdrum day on Capitol Hill turned into a firestorm as Majority Leader Harry Reid proposed his own plan to extend unemployment benefits and effectively blocked Republicans from having further say in the matter.

After several days of debate over how to pass a three-month extension of the Emergency Unemployment Compensation program, Reid side-stepped negotiations with Republicans and offered a plan of his own to extend benefits through mid-November. In doing so he used a procedural tactic known as “filling the tree” to block Republicans from proposing any further amendments.

When Reid said at a Thursday afternoon press conference he was “cautiously optimistic,” that a long-term deal would soon be announced, what he came up with isn’t what Republicans had in mind.

“Sen. Reid announced today that he will obstruct ALL [sic] Republican amendments,” Don Stewart, a spokesman for Mitch McConnell, told BuzzFeed in an email. “It’s a real challenge to find a bipartisan accomplishment when one person shuts out the entire side of the aisle.”

“This is crassly political,” Sen. Bob Corker (R-Tenn.) said. “They want to have something to talk about on the Sunday morning programs.”

Make no mistake about it: Harry Reid blew up any momentum that had developed on this bill. The act of blocking amendments is the main reason that Republicans have to resort to cloture fights, in order to get Reid to stop blocking minority input on legislation.  It’s the flip side of the filibuster fight, one that the media doesn’t cover nearly as much as it does with the supposed abuse of the filibuster itself.

Corker is absolutely right — this move is nothing but crassly political. Any amendments filed would still have to pass on a floor vote, so if they are too radical for Democrats, they won’t fly anyway. Why block them at all, then? In this case, Reid doesn’t want this issue to get resolved, because Democrats want to use it all year long in the run-up to the midterm elections. They are scared to death of what ObamaCare means for Senate control, and the surprise vote that allowed debate on the UI bill must have stunned Reid into thinking one of his alternate issues might end up defused long before they needed it to cast the GOP as uncaring about the chronically unemployed.

The question Republicans should ask is this: what is Harry Reid afraid of in potential Republican amendments? That they might actually carry some Democrats, and demonstrate that Reid is an extremist?