Iran’s parliament has approved a measure to close the Strait of Hormuz after the United States launched military strikes on its nuclear facilities over the weekend. The final decision rests with the country’s Supreme National Security Council and Supreme Leader Ayatollah Ali Khamenei – but the move has already deepened fears for the global energy trade. In this explainer, we examine why this matters and what the implications of a blockade would be. Where is the Strait of Hormuz? Why is it so...