Roughly 20 million barrels of oil per day — about 20% of global petroleum liquids consumption — moved through the Strait of Hormuz in 2023, according to the U.S. Energy Information Administration.
The Strait of Hormuz is only about 21 miles wide at its narrowest point, with shipping lanes just two miles wide in each direction.
Iran's coastline runs along the entire northern side of the strait, and Tehran has repeatedly threatened to close it in response to sanctions or military action.
Under the UN Convention on the Law of the Sea, ships enjoy a right of 'transit passage' through international straits like Hormuz — a right the US Navy has enforced for decades.
The US Fifth Fleet, headquartered in Bahrain, has patrolled the Persian Gulf since 1995 and routinely escorts commercial tankers through the strait.