The Strait of Hormuz is usually described as a chokepoint. Today, it is more than that. It is the hinge point between war and peace in the Gulf.

Roughly a fifth of the world’s oil and gas trade passes through this narrow waterway. When it was secure, the global economy barely noticed it. As soon as it was threatened, prices jumped, shipping costs rose and military tensions spread beyond the region. Today, the issue is even larger than economics. If the status of the strait is left unresolved,...