But Trump’s president now, and he has to make a choice. In the face of a clear, unacceptable provocation, can he actually draw lines the Saudis can’t cross? Can he take actions to demonstrate that America isn’t bound to Saudi money? Can he even use rhetoric half as extreme as he used against Canada this summer?

It’s not as if we don’t have cards to play. Yes, the Saudis spend immense sums on American arms, but they’re also dependent on American cooperation to sustain their military operations. Yes, the Saudis are extraordinarily wealthy, but our economic power dwarfs theirs. They fear Iran more than we fear Iran.

At a minimum, we can and should stop facilitating the Saudi bombing campaign in Yemen, a campaign that depends on American weapons and American help and is murderously indiscriminate. At a minimum, we can demonstrate to the Saudis exactly how much they depend on us to confront Iranian aggression. They are the junior partner in this alliance, and junior partners cannot be permitted to go “rogue.”