Donald Trump’s war on Iran is backfiring in a critical area: Iran is exporting more oil through the Strait of Hormuz than before. The Wall Street Journal reports that Iran has taken control of the key waterway and effectively shut out the rest of the oil-producing countries in the Persian Gulf. Since the war began February 28, Iran has loaded seven tankers, and in the past week, tankers have loaded an average of 2.1 million barrels of oil each day, more than its 2.0 million barrel average in February. China, one of Iran’s biggest oil importers, appears to be taking most of the oil. And almost all ship traffic moving across the strait is “linked to Iran or China,” Christopher Long, head of intelligence at U.K. maritime-security company Neptune P2P Group, told the Journal. Trump has claimed that it’s safe for ships to traverse the strait and tried to bully oil companies into challenging Iran, to no avail. He hasn’t followed up on his offer to use the U.S. Navy to escort ships, and even if he did, there are now more stopped ships than the Navy can handle. And now, Iran has reportedly begun laying mines in the strait, complicating naval traffic further. “If for any reason mines were placed, and they are not removed forthwith, the Military consequences to Iran will be at a level never seen before. If, on the other hand, they remove what may have been placed, it will be a giant step in the right direction!” Trump angrily posted on Truth Social Tuesday. On Wednesday, the U.S. Central Command said it had destroyed 16 Iranian mine-laying ships. But none of that seems to have affected Iran’s control of the strait, and its ability to export oil. It’s a scenario that the U.S. should have seen coming, considering that closing off the strait has been threatened by Iran before and is a long-standing pillar of Iranian defense strategy. To make matters worse, the U.S. decommissioned four anti-mine ships stationed in the Persian Gulf in January. Right now, Iran is controlling one of the world’s most critical shipping lanes for oil, and is exposing Trump’s lack of planning for this war.