President Trump is pairing his Iran blockade with a sales pitch: Countries squeezed by the Strait of Hormuz — especially China — should buy more oil from the U.S. instead.Why it matters: The U.S. rise to become the world's largest oil and gas producer — and largest exporter of liquefied natural gas — provides geopolitical leverage that Trump is attempting to wield.Driving the news: "China can send their ships to us. China can send their ships to Venezuela," Trump said on Fox's "Sunday Morning Futures."And he claimed in a Saturday social media post that "empty Oil carrying ships from many Nations are all heading to the United States of America to LOAD UP with Oil."Reality check: The U.S. is already among the world's largest oil exporters.But it doesn't have the capacity to come close to replacing the massive flows normally moving through the Strait of Hormuz.And crude oil is not always interchangeable. Refiners in different regions use different types of oil. The U.S. exports mostly light grades.The big picture: U.S. crude oil export volumes bounce around but generally run in the range of 3.5 million to 4.5 million barrels per day.They were 3.9 million barrels per day in January, the last month with robust federal data. More recent — and preliminary — weekly data show 4.2 million the week of April 3.Threat level: The Iran war has halted 20 million barrels per day of crude and petroleum products that typically travel through the Strait, which handles about a fifth of the global oil trade.Only a fraction of that is replaced by crude volumes getting onto the market via Saudi Arabia's east–west pipeline to the Red Sea.Persian gulf oil producers, lacking export routes, have cut output by 8–10 million barrels per day by some estimates. Zoom in: U.S. exports of petroleum products like gasoline, jet fuel and diesel have been generally rising for years.They hit a new peak of 7.9 million barrels per day the week of March 27, per weekly data from the Energy Information Administration. However, this quick-turnaround data is notoriously noisy, and more robust numbers arrive after a lag.What they're saying: "While weekly figures are volatile, multiple sources have reported U.S. product exports increasing to Asia, Africa and other areas," Mason Hamilton, a top researcher with the American Petroleum Institute, noted on X recently."Trade flows have also become increasingly atypical, with reports U.S. Gulf Coast gasoline moving to Australia and East Coast jet fuel heading to Europe, highlighting the global pull on U.S. products amid ongoing supply disruptions," he posted.What we're watching: The crisis could spur fresh investment in Gulf Coast infrastructure projects that would expand U.S. oil export capacity over the longer term.The bottom line: U.S. exports can help ease the global supply crunch, but they're nowhere near a solution.