As you note, Shannen, we agree on a lot here. Senate Republicans are certainly within their rights to abolish judicial filibusters. (I think they would probably be within their rights to abolish filibusters altogether by a simple majority vote.) And neither of us knows for sure how a fight over a Supreme Court nominee would go under the current rules. Even on the politics, I’m not sure how much we disagree. I’m not contesting your claim that the Democrats have a high level of commitment to beating conservative nominees; so far at least, you have not contested my contention that the filibusters of judicial nominees have been politically costly for Democrats. (These views are perfectly compatible with each other: One could argue that the fact that Democrats persist in filibustering even though they are paying a price for it shows how committed they are.) Nor have you contested my contention that we have reason to think that a Supreme Court filibuster would be even costlier for them.

If we had a situation where the Democrats persisted in filibustering a Supreme Court nominee in the face of public opposition–and if the filibuster could not be broken no matter how intelligently and forcefully the Republicans fought it (and I would hope that under these circumstances they would do rather more than they have done to date). . . . Well, then my argument against ending the filibuster would lose much of whatever force it has. And that would probably be the most propitious time to impose a rules change.