In the travel ban litigation, the courts asserted a new power to disregard long-established and long-accepted formal law if the president’s personal words created a basis for mistrusting his motives. In response to the danger posed by Trump, other holders of American power are tempted to jettison their historic role too, and to use any tool at hand, no matter how doubtfully legitimate, to stop him. In order to save the constitutional system, its defenders are at risk of corroding it.
