The Strait of Hormuz – a narrow, indispensable artery through which nearly a fifth of the world’s oil and a third of its liquefied natural gas (LNG) flows– stands on a cliff. As geopolitical tensions intensify across the Middle East, fuelled by escalating Iran-Israel tensions and the shadow of direct United States (U.S.) involvement, the once-unthinkable threat of its closure looms larger than ever with Iran’s threat to close or block the Strait. In spite of the catastrophic global implications of such an act, the volatile depths of this potential crisis will be explored, unravelling the motives that could push Iran to choke this global lifeline, exposing the monumental security and geopolitical fallout, and revealing the catastrophic economic shockwave that would consume nations far beyond the region.