For the first time since 2006, the Lebanese are again facing the prospect of a devastating war with Israel, on the back of the current conflict in Gaza. Much of the population does not want, and knows it cannot afford, such a war. Lebanon is still in the throes of an economic collapse that began in 2019. Yet Hezbollah, which dominates Lebanon’s political scene, seems moved less by what its countrymen want than by the strategic priorities of its sponsor, Iran. The Iranians have worked painstakingly in the past decade to build up a redoubtable deterrence capability on Israel’s borders with Lebanon, Syria, and Gaza. Hezbollah realizes that a full-scale conflict might weaken its hold over Lebanon and will try to avoid such an outcome. But ultimately, the party will follow Iran’s lead. Earlier this year, Hezbollah’s secretary general, Hassan Nasrallah, began referring to a “unification of the fronts” strategy. The idea was that Iran-backed armed groups, joined into the so-called Axis of Resistance, would coordinate operations against Israel, especially in defense of Muslim holy …