I've received some email solicitations to sign on to the Law Professors' Letter on Judicial Nomination Filibusters. I hope the 'nuclear option' doesn't pass, because I think the judges being bottled up are by and large either unfit or such extremists as to have no place on the federal appellate bench. (Indeed, I think the Democrats' allowing DC Circuit nominee Thomas B. Griffith to be confirmed is very unfortunate as he's simply too slipshod to be trusted with a lifetime appointment.)
But I'm not going to sign this letter because I don't agree with how it frames the issue. For me, the bottom line is that the filibuster is a tainted institution. It is politically convenient now, and in service to what I think is a very very good cause, but its history is too intertwined with the fight against civil rights for me to try to wrap it in the flag. Furthermore, as a general matter, one of my main beefs with the Senate is that it is too counter-majoritarian due to the radical population imbalances between the states, many times greater than anything imagined by the Framers. The law professors' letter praises the counter-majoritarian role; I think it is quite suspect. Indeed, if the Senate were more representative by population, I don't think there would be a GOP majority. It would certainly be small at best. Recall that the House is a lopsided as it is only due to gerrymandering.
So the filibuster is convenient now. There is some virtue in not letting majorities trample impassioned minorities. But not always. I'm not sure if I have a fully worked out general metric for when filibusters are reasonable and when they are abusive. The size and permanence of the change are relevant. The passion of the minority is relevant. I'd say that the nature of the change matters too — things than enhance freedom should be less subject to it — but that's such a contestable term that I can't put much weight on it.
There are some complicated issues about how many votes, under the Senate's rules, really should be required to pass the 'nuclear option'. These aren't, however, constitutional issues, and I don't pretend to be expert in the Senate's rules of procedure. Ultimately, for me this is a political issue about how much pain the majority wishes to inflict on the minority, and how much the minority can inflict pain back, either by bringing the Senate to a halt, framing the issue as the destruction of a hallowed tradition of free debate, or stomping on the minority when the parties change roles.
Pragmatically, I think if the GOP does this, they'll rue the day, and so meanwhile will the rest of us. But that's not the argument in the letter.