U.S. President Donald Trump threatened to impose new tolls in the Strait of Hormuz last weekend, sparking worries that the practice of charging to pass through critical waterways could spread — with devastating consequences to the global economy. Iran has blocked the strait for much of the war, reportedly charging tolls as high as $2 million US for ships it allows to pass.

Iran and the U.S. both threatened to tax ships crossing the world's most critical oil chokepoint — an action experts say violates international law.

U.S. President Donald Trump threatened to impose new tolls in the Strait of Hormuz last weekend, sparking worries that the practice of charging to pass through critical waterways…