Following renewed U.S. military strikes on Iran and reports of merchant ships being hit near the Strait of Hormuz, President Donald Trump announced on Fox News that the United States would act as a “guardian” of the waterway and impose a 20 percent toll on cargo passing through it. U.S. Secretary of State Marco Rubio responded to that proposal by stating that no nation may levy fees on an international passage, a principle that Iran’s foreign minister has partly endorsed while disputing the specific percentage. The dispute centers on the narrow shipping lane that carries a large share of the world’s traded oil and gas, and the toll plan has drawn concern from Australian officials who warn it could raise shipping costs and ultimately hit household budgets. The situation matters because it represents a shift in how major powers may use control of strategic sea routes as economic leverage, affecting global energy prices and trade stability.