"One of the reasons that he's not doing anything, I think, is because he doesn't know what to do. He and the Republican majority in the Senate have tied themselves so closely to Trump that they can't cross him, so that Trump has painted himself into a corner on all of this, and he's taken McConnell with the Republicans with him."

"[McConnell] is running scared a little bit here because he sees no exit from this. And without any exit, he's figured there's nothing he can do, and anything he can do would probably hurt the Republican majority, and he wants to avoid that at all costs.

Bill Straub: "It's a combination of things. McConnell, more than anything else, is interested in power. And he's had power here for several years in the majority now, and he doesn't want to lose it. At the same time, he doesn't want to turn on President Trump, because there's still a lot of things that Republicans want to do and they'll need Trump's support to do that. It's also a political calculation. If he was to call up for a vote, for instance, and a lot of Republicans voted to override [Trump's] veto, then, next time when they run, in 2020, [Trump has] gotten enough support where he could find somebody to primary them. And that would cause a lot of chaos within the Senate ranks. So there's a lot of things going on here.

You can look at this as McConnell’s effective legislative pragmatism at its best. Or, his cold-blooded political cynicism at its worst. Either way, it’s time to talk about why this government shutdown belongs to Mitch McConnell, too.

How did McConnell respond? Well, he’s said pretty much nothing about the government shutdown for days. But he made his shutdown position very clear earlier this month, saying: "The Senate will not waste its time considering a Democratic bill which cannot pass this chamber, and which the president will not sign."

"He's figured there's nothing he can do, and anything he can do would probably hurt the Republican majority, and he wants to avoid that at all costs."

On McConnell's tactics, and his responsibility for the shutdown

Alec MacGillis: "He often likes to project onto the Democrats the kind of tactics and accusations of obstruction that really best describe his own behavior as Republican leader in the Senate all these years. There are a lot of culprits in bringing Washington to the place it is now, but McConnell's role in the rise of the obstruction and gridlock that we've had in Washington, and a degrading of norms in Washington, just cannot be overstated. If you look objectively at the rise of the use of the filibuster and all of these other blocking tactics in his time as Republican leader, the fault and the responsibility very clearly lies with him. And many arbiters of Washington have basically come to that conclusion.

"He played an enormous role in the election of Donald Trump. To the extent that the shutdown is brought to us by Donald Trump, Mitch McConnell is responsible for it because of his own role in Trump's election. He helped elect Trump in any number of ways. First of all, of course, with the blocking of Merrick Garland's nomination, refusing to even hear that nomination, to entertain it at all — which is a complete break with norms in Washington — he gave Trump a huge hand by giving Republicans a reason to rally around Trump in the fall. He also helped elect Trump by basically feeding this rise of Republican opposition to Obama and sort ceding this kind of Tea Party-ish conservatism."

On the evolution of Mitch McConnell

MacGillis: "Mitch McConnell was, back in the 1960s and '70s, a very moderate Republican. He was a staunch defender of abortion rights when he was the county executive in Louisville and Jefferson County, Kentucky. He sought the AFL-CIO's endorsement back then. He was very pro-civil rights. He was very much on the moderate side of the Republican party in that era. He then swung very sharply, very quickly to the right after he got to Washington. The election in 1984 was for him a very narrow victory, in the same year where Ronald Reagan won a huge victory in Kentucky in 1984, Mitch McConnell barely won his first Senate race. It surely looks like he concluded that if he wanted to have easier victories from there on, he was going to have to sort of shift to the right and get in line with the rest of the conservative Republican party in the South.

"With McConnell, even more than with other politicians, it is all about the win. It's all about setting yourself up to win the next election. It's the permanent campaign mindset where everything is about, 'How are you going to win the next time? How are you and your party going to win the next cycle?' It's that rather than what you actually do in power. He has shown very little interest in a whole swath of issues that a lot of conservatives care about, including immigration. Back in 2007, when George W. Bush was first trying to fix our immigration system, there was a big push back then, big legislation that came before the Senate, and McConnell then, as Republican leader, completely held back from the whole debate on that vote and just showed no leadership whatsoever. ... He's not driven by ideology. The issues, the things that he actually cares about are the court and campaign finance reform, because those are issues that actually play a role in winning elections. It's the issues that are all about the political game itself that he cares about."

On whether McConnell's moves indicate a subordination of the Senate to the president

Jasmine Farrier: "The majority leader position would be to stick with the president in this circumstance. It's very hard to put a mathematical equation on it. Every single member of Congress has multiple hats. They have to represent their constituents, the majority of the people who got there. They have to represent their party. They also have issues that are near and dear to them. In the case of Leader McConnell, he also does have a major institutional role. He does profess a worshipfulness of Henry Clay, of compromise, he's not a gleeful leader in this shutdown. ... I don't think we will ever hear Leader McConnell say that this shutdown was a good move.

"Henry Clay was considered the great compromiser. He helped at least three major compromises before the Civil War that some historians believe gave the Union 10 full years to prepare for inevitable secession. Henry Clay is very different. from Sen. McConnell's point of view, than, say, Sen. Paul. So Sen. Paul's maiden speech on the Senate floor was actually critical of Henry Clay, saying why compromise over things you believe in? Sen. McConnell has always said that he aspires to be a Henry Clay-like figure, using institutional power for national good."