Trump's second term has broken presidential norms at a breakneck pace, but his demand that Republicans initiate the "nuclear option" of ending of the filibuster on Thursday to reopen the government is a Pandora's box senators would rather keep closed.
Why it matters: Overhauling Senate precedent in such a powerful way is great when you're the party in power — but it could make life miserable for Republicans if Democrats retake control.
