In response to Iran’s closure of the Strait of Hormuz, which it said was due to unauthorized transit, President Donald Trump announced that the U.S. military would take control of the waterway and impose a 20 percent fee on all cargo passing through. Trump’s stated plan to block Iranian ships or customers from entering or leaving the strait came after three consecutive nights of U.S. airstrikes on multiple Iranian cities and ports. Iran’s army spokesperson vowed not to reopen the strait through force, while Iran also launched retaliatory strikes toward Gulf nations. The standoff matters because roughly 20 percent of global oil transits the strait, and its closure had already driven up oil prices by 50 percent.