In Dallas on a September night, Donald Trump gathered his party around a promise and a warning — five thousand dollars for every American adult if Republicans hold power, and two hundred fifty years of national consequence if they do not. The gathering, framed as an unprecedented midterm convention, revealed both the enduring gravity of Trump's hold on Republican energy and the quiet anxiety beneath it: a party whose most powerful draw will not appear on the next two ballots. History rarely moves in straight lines, and the distance between a bold pledge and its fulfillment is where politics mo