Sen. Mitch McConnell was jolted with a fresh reminder of President Trump’s capriciousness last month: The majority leader persuaded Republican colleagues to take a politically difficult vote to temporarily fund the government, but not a border wall, only to see Trump withdraw support — initiating the longest shutdown in history. House Republicans learned the same lesson early in Trump’s presidency when he rallied them to repeal Obamacare, then described their effort as “mean.”
