President Obama spoke at a fundraiser this week and mentioned a variety of ways policymakers need to improve the American political system. “There are all kinds of reforms that we need to do,” the president said , including “how a filibuster works.”

Obama didn’t clarify exactly what kind of changes he’d like to see, but to appreciate just how foolish filibuster abuses have become in the contemporary Senate, consider what transpired in the chamber yesterday.

Senate Republicans filibustered an $85 billion tax cut package after Democrats refused to allow votes on their amendments. Cloture on the tax cut measure failed 53 to 40. It needed 60 votes to advance. Illinois Senator Mark Kirk was the only Republican to vote yes. The grab bag of more than 50 tax breaks, which expired at the end of 2013, includes breaks for research and development, mortgage forgiveness and the deductibility of state and local sales taxes.

Remember, we’re talking about tax breaks that Republicans support. But when it came time to advance the legislation, 40 GOP senators voted and 39 of them decided to filibuster the bill.

So why did Republicans balk? The answer has to do with process: they said they wanted to vote on a series of amendments to the bill, and when Senate Majority Leader Harry Reid (D-Nev.) refused, they decided to at least temporarily block the legislation they like.

Do the GOP senators have a legitimate gripe? Not really, and it’s important to understand why.

In this case, Sens. Ron Wyden (D-Ore.) and Orrin Hatch (R-Utah) worked out a bipartisan compromise on a series of tax breaks. Both sides had to accept concessions in order to reach the bipartisan deal, but the agreement came together.

Senate Republicans are now saying the bipartisan compromise isn’t quite good enough without some amendments. For Democrats, this is effectively breaking a deal – if members of both parties already negotiated an agreement, the majority doesn’t see a reason to move the agreement to the right.

At this point, you might be thinking, “But since Democrats are in the majority, maybe they should just allow the amendments, defeat them, and allow the bill to move on.” And in practice, that’s pretty much what Harry Reid concluded, too, telling Republicans that he would allow votes on amendments so long as they related to the legislation itself.

Yesterday, GOP leaders said that wasn’t good enough. They want to use unrelated amendments as campaign tools and are infuriated when the majority won’t play along.

And so for the second time this week , Republicans killed a bipartisan agreement that they actually liked.

Yesterday’s filibuster was not a fatal blow – both sides expect to revisit the tax breaks soon – but it was a reminder as to just how dysfunctional Capitol Hill has become.