Just hours after a brief reopening had raised fragile hopes of progress in U.S.–Iran negotiations, Iran shut the Strait of Hormuz once more on Saturday, April 18. Tehran cited the continued U.S. naval interception of ships leaving its ports as justification for the closure, warning of further disruptions if the blockade is not lifted.
The move was punctuated by violence. According to Britain’s maritime authority, Iranian Revolutionary Guard gunboats attacked a tanker located northeast of Oman. The crew was reported safe, but the incident underscored the rapidly escalating danger in one of the world’s most critical energy chokepoints. Iran’s Supreme Leader Khamenei issued fresh threats, declaring that the United States “cannot impose a siege” on the strait.
The Strait of Hormuz handles roughly a fifth of the world’s daily oil supply. Every closure — even a brief one — sends shockwaves through global energy markets and raises the spectre of a wider regional conflagration.
