Since the Iran war began late last month, it has threatened shipping across the Middle East’s two most important maritime chokepoints – the Strait of Hormuz and the Bab el-Mandeb – through which much of Asia’s energy imports and manufactured exports flow. For Gulf states and their major trading partners in Asia, the conflict is forcing a hard question: what, if anything, can protect supply chains if US security guarantees can no longer be taken for granted? Analysts say the usual answers –...