Today was a national tragedy of the first order. Tonight we discuss: * the many crimes that definitely were committed, and certain other crimes -- particularly seditious conspiracy -- that may have been committed (and how that relates to the First Amendment Brandenburg test) * the bizarre and indefensible lack of a strong police presence and a proper National Guard response (including an unpacking of the legal authorities governing control over DC's guard) * some familiar -- and some not-so-familiar -- interpretive questions associated with the 25th Amendment (including not just the role of "Acting" secretaries, but also the question of what happens if the president's "rebuttal" letter is followed instantly by the firing of all the secretaries who signed the original letter) * impeachment issue, including the prospect of proceedings lasting beyond January 20th...and the possibility of an outcome permanently barring Donald J. Trump from office