I'm very worried about preemptive announcements of how his presidency will fail. That's the sort of thing that makes people resent "elites" in the first place! I think that the best thing is for the liberals to marshal their political support while saying they'll consider bills trump proposes. Keep all the leverage they can while not signaling that they'll be out to sabotage trump. Saboteur government, like with the republicans under Obama, didn't work, and I hope the Democrats doesn't try it.