For most of the post-revolution period, Iran’s maritime threat was a Hormuz threat. Its proxies were land-based, oriented against Israel and US forces in Iraq and Syria. Sometime around the middle of the last decade, Iran began transferring serious naval capability to the Houthis in Yemen, and the maritime threat picture extended to Bab el-Mandeb. The campaigns of recent years demonstrated what that capability looks like in practice. The Iranian theory was that a distributed maritime threat across two chokepoints multiplied leverage. The actual result was that Iran lost control of half its maritime card.

The Strait of Hormuz has a sister chokepoint at the other end of the Arabian Peninsula. Bab-el-Mandeb, the narrow passage between Yemen and Djibouti that connects the Red Sea to the Gulf of Aden, carries the maritime traffic of the Suez Canal route — container ships, bulk carriers, tankers moving between Europe and Asia, and LNG vessels serving European regasification terminals. When Houthi forces in Yemen began attacking commercial shipping in the Red Sea in late 2023, they demonstrated that Iran’s sphere of proxy influence could threaten two of the world’s most critical maritime corridors simultaneously.