Here are the arguments for why Senate Democrats should filibuster:

1. Garland. They need to protest what Republicans did to Judge Garland’s nomination last year. Democrats need to take extraordinary action to make it clear the extreme wrong of the Republican refusal to hold hearings.
2. Gorsuch. Judge Gorsuch will be such a conservative justice that Democrats need to do all they can to try to stop his nomination.
3. The Base. The progressive base and liberal pressure groups are energized and are demanding that Democratic senators do all they can to stop the nomination. Even if a filibuster is unlikely to prevent Gorsuch from taking his seat, it could be seen as a partial victory and might further energize the base for future battles.
4. Long Game. The most likely consequence of a filibuster—i.e., the “nuclear option” of a Senate rules change that eliminates the filibuster for Supreme Court nominations—is not as bad as it sounds. A straight majority vote process might even allow a future Democratic-controlled Senate to get a more liberal justice onto the Court.

And here are the arguments for why Senate Democrats should not filibuster:

1. Futility. The Republicans have the votes to change the rules, eliminate the filibuster, and put Gorsuch on the Court. Why not focus on battles that can be won?
2. The Next Justice. Gorsuch is conservative but widely respected and clearly qualified. And he is taking the seat that had been occupied by the conservative Justice Scalia. Why not preserve the filibuster for a future court battle in which the nominee might be more problematic (less qualified and/or more extreme) and/or the current ideological balance of the Court will be at stake?