A narrow waterway located at the mouth of the Red Sea has provided an escape hatch for a sizeable chunk of the Middle East’s oil. That lifeline is now looking increasingly shaky.

Houthi control of a Red Sea port brings Tehran closer to claiming another critical waterway.

The Houthis do not control the coastal areas bordering Bab al-Mandab, but they hold the large port city of Hodeida further north.