CAIRO: International observers have tended to explain the Houthis’ attacks on Saudi airports and other civilian targets in recent days through the prism of military strategy, regional rivalry and the militia’s alliance with Iran. But behind the missiles and drones lies an ideology that divides the world into allies and enemies, claims exclusive religious legitimacy and presents confrontation as a sacred duty. From a network of religious study groups in northern Yemen, the Houthis, also known as
