In 1987, an Iraqi warplane attacked an American Navy frigate, the Stark, on patrol in the Persian Gulf. Accepting Saddam Hussein’s explanation that the attack, which killed 37 sailors, had been an accident, American officials promptly used the episode, which came at the height of the Iran-Iraq war, to ratchet up pressure on Tehran. The incident provided the impetus for what became a brief, and all but forgotten, maritime war between the United States and Iran.

Last week, someone — precisely who remains to be determined — attacked two oil refineries in Saudi Arabia. American authorities have been quick to blame Iran, and the possibility of a violent confrontation between the two countries is once again growing. Before making a decision on whether to pull the trigger, President Trump would do well to reflect on that 1987 episode and its legacy.

Back then, the United States had become involved in the very bloody and seemingly interminable Iran-Iraq war, which Hussein had instigated in 1980 by invading Iran. As that war turned into a brutal stalemate, President Ronald Reagan and his advisers persuaded themselves that it was in America’s interests to come to Iraq’s aid. Iran was the “enemy,” so Iraq became America’s “friend.”

After the Stark episode, American and Iranian naval forces in the gulf began jousting, an uneven contest that culminated in April 1988 with the virtual destruction of the Iranian Navy.