When I was in college, I remember massive protests on my campus against the Bush administration's decision to invade Iraq, and at the time I remembered thinking that the protests were rather pointless; the decision had already been made, and there was no way to undo it. The Congress had already approved an authorization for use of military force so broad that it arguably covered the Iraq invasion and subsequent occupation, and there was no contingent in Congress that would hold the President accountable for starting an illegal war. As I saw it, you couldn't stop the war from starting; the best you could do would be to end it sooner by supporting the President's opponents and removing Bush from power. We all know how that turned out.
I listened to some of the Kavanaugh confirmation hearings earlier today, and then turned them off, and haven't given them much thought since, for essentially the same reason: Republicans have the votes and Democrats don't. There is no way to stop the confirmation, and nothing said in the hearings will in any way affect Kavanaugh's votes once he is on the Court. This fight was lost 18 months ago. It would be considerably wiser, in my opinion, to prepare for the next fight rather than get bogged down in one that is already over.