Tonight on the Last Word: Donald Trump becomes the only president to be impeached twice. Also, Trump’s second impeachment is the most bipartisan in U.S. history. Plus, Sen. Mitch McConnell blocks the effort to begin Trump’s impeachment trial in the Senate until after Joe Biden’s inauguration. And Republican Rep. Paul Gosar’s siblings call for his removal from office. Rep. Adam Schiff, Alex Wagner, John Heilemann, Sen. Amy Klobuchar and Tim Gosar join Lawrence O’Donnell.