Iran’s escalation of hostility in the Gulf of Oman is a dangerous situation. Targeting civilian oil and chemical tankers, Iran is threatening free passage of a critical global trade route.

President Trump’s response must be measured so as to defuse, rather than further escalate, the tension. But he may be tempted to avoid any confrontation for fear of causing oil prices to spike. Worrying too much over short-term oil prices would be a mistake.