The United States is rushing the 31st Marine Expeditionary Unit toward the Strait of Hormuz as it weighs deploying Marines to physically secure the world’s most important oil chokepoint, after Iran’s closure of the waterway sent energy prices soaring and left hundreds of tankers stranded. Aboard the USS Tripoli, the 2,200-strong rapid-response force could seize or hold Iranian islands like Kish and Qeshm, launch amphibious and air raids with F‑35Bs and MV‑22s, and help neutralize missiles, drones and sea mines that now threaten global shipping. U.S. officials say the MEU gives President Trump new hard-power options to pressure Tehran and potentially reopen the strait, even as key European allies refuse to join a U.S.-led mission, leaving Washington increasingly isolated in a high-stakes battle over the world’s vital energy artery.