President Donald Trump told reporters at this week’s NATO summit in Ankara that he is “number one on the kill list” for Iran. While Trump was in Turkey, a member of Iran’s parliament publicly proposed missile strikes on his location there. Earlier this year, Iranian state media broadcast the photograph from Butler, Pennsylvania, with a warning that the next shot will not miss, and regime officials have spent months vowing revenge for the death of Ayatollah Ali Khamenei.

None of this should be dismissed as regime theater. It should force Washington to confront a question it has never clearly answered: How should the United States treat a foreign state’s attempt to kill the president?