What purpose does the Senate serve? As the Wall Street Journal reports today, the relatively progressive Democrat Kyrsten Sinema has a very clear grip on that answer — and doesn’t appear to be budging on it, either. Despite massive pressure to bend the rules for parts of the agenda from Nancy Pelosi and Chuck Schumer, Sinema insists that the rules aren’t the issue.

Instead, the issue is the agenda, and the way it’s being pushed:

House Democrats have passed bills on voting rights, immigration and gun control, but all are expected to be blocked in the 50-50 Senate unless the rules are changed. Ms. Sinema said that is a problem with the senators, not the rules.

“When you have a place that’s broken and not working, and many would say that’s the Senate today, I don’t think the solution is to erode the rules,” she said in an interview after two constituent events in Phoenix. “I think the solution is for senators to change their behavior and begin to work together, which is what the country wants us to do.”

In some ways, Sinema might be an even stronger obstacle to rule changes than Joe Manchin. The West Virginia Democrat wants to maintain the filibuster, but he’s been suggesting “reforms” to it that could unlock full majoritarian domination in the upper chamber. As Allahpundit has noted with considerable frustration, Manchin’s been slippery on the parameters of his defense, raising questions about just how stalwart Manchin will be.

In contrast, Sinema has diagnosed the problem correctly, and in a way that the media keeps ignoring. The problem isn’t the filibuster, and it’s not intractable partisanship per se. The problem arises from efforts by the controlling party to cut the opposition completely out of the loop when it comes to drafting legislation.

Both parties have been guilty of this at times, but that’s very clearly the case this year, as Biden’s promises of bipartisanship belie the process that he, Pelosi, and Schumer have used in drafting these bills. Democrats are cooking them up as a fait accompli and then trying to shove them through by brute majoritarian force. Republicans, having been given no opportunity to help shape these initiatives, have zero reason to invest themselves in them.

Sinema remains adamant that the solution lies with the people rather than the rules. Although she hasn’t spoken as much about the filibuster as Manchin, Sinema is taking a harder line, especially on the idea of exceptions:

Ms. Sinema supports both pieces of legislation, but she has signaled no interest in carving out a special exception to the 60-vote threshold for voting-rights bills, as some Democrats have suggested.

The Senate’s job is “to craft bipartisan solutions to solve the challenges we face in our country,” she said. Asked how she thought both parties could come together, given how polarized the country has become, especially over elections, she responded: “I actually think I’ve got a pretty good track record.”

That’s an impressive commitment to principle. Agree or not with Sinema on policy very often, this should generate respect for her independence across the political spectrum. Let’s hope it lasts, and let’s also hope that the media starts picking up on Sinema’s definition of bipartisanship.