At the narrow throat of the Red Sea, Yemen's Houthi militia has seized islands and coastlines that give it leverage over one of the world's most consequential shipping lanes — and in doing so, has placed Egypt in the uncomfortable position of a bystander whose livelihood depends on a corridor it cannot control. The Houthis say they seek only to punish Saudi Arabia, but selective disruption in a chokepoint is rarely contained, and Egypt's Suez Canal revenues have already fallen by billions. What unfolds now is an old story in new geography: a small armed movement reshaping the economic fate of