President Trump says the United States is “locked and loaded” to retaliate against whoever struck Saudi Arabia’s oil refineries on Saturday. But before American forces rain “fire and fury” on Iran, there are some urgent questions that must be answered.

Are we quite sure that Iran is the culprit?

Iranian culpability certainly seems the most plausible explanation for the refinery attack. But given the utter untrustworthiness of both the Trump presidency and the Mohammad bin Salman’s Saudi government, it seems wise to demand certainty, not plausibility. How confident are U.S. analysts that the attack was ordered from Tehran, rather than by an Iranian proxy acting for its own motives?

Where’s the treaty obligation?

The United States and Saudi Arabia have committed themselves to many agreements, formal and informal, since the famed meeting between President Franklin Roosevelt and King Abdul Aziz ibn Saud in February, 1945. Yet the two countries have never quite bound themselves to an unconditional mutual-defense treaty in the way that, say, the United States and Japan have done. When Saddam Hussein invaded Kuwait in August 1990, the U.S. made clear that an attack on Saudi Arabia would draw a U.S. response—but that decision was based on the perception at the time that U.S. interests were at stake, not upon any treaty duty.

Has Congress spoken?

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