TEHRAN, July 12 — On April 28, 2025, Iran’s Islamic Revolutionary Guard Corps navy announced the closure of the Strait of Hormuz until further notice, according to state media reports. The announcement came amid heightened tensions over Iran’s nuclear program and recent U.S. sanctions reimposed in 2018 under the Trump administration. More than a year later, the strait remains closed, and the practical consequences for global energy markets are still unfolding.
The Strait of Hormuz is a narrow waterway between the Persian Gulf and the Gulf of Oman, approximately 33 kilometers wide at its narrowest point. Think of it like a highway on-ramp for the world’s oil supply — except that on-ramp is only about 20 miles across at its tightest squeeze.
According to the U.S. Energy Information Administration, roughly 20 million barrels of oil pass through daily, representing about 20% of the world’s petroleum consumption. In plain terms, that’s one out of every five barrels of oil the planet uses every single day. The IRGC is a branch of Iran’s military established after the 1979 Islamic Revolution.
It has previously threatened to close the strait in response to sanctions or military pressure. The practical upshot of this closure is a potential disruption to global energy markets, with impacts on oil prices and shipping insurance rates already being felt by traders and logistics firms.
The strait is bordered by Iran to the north and the United Arab Emirates and Oman to the south. Both Oman and the UAE maintain diplomatic relations with the U.S. and Iran, which complicates any potential response from regional allies. The United Nations Convention on the Law of the Sea, which Iran has not ratified, guarantees freedom of navigation through international straits.
Here’s what it means: under international law, ships have a right to pass through, but Iran isn’t a signatory to that treaty, so it doesn’t recognize that obligation. The U.S. Fifth Fleet, based in Bahrain, has not yet issued an official response to the closure. The fleet is the primary American naval force in the region, responsible for protecting shipping lanes and responding to threats.
Its silence so far leaves open questions about how the U.S. might respond if the closure continues to affect global oil supplies. What to watch next: whether the U.S. administration under President Donald Trump, with Vice President JD Vance and Secretary of State Marco Rubio, takes any formal action — diplomatic or military — to reopen the strait.
Also worth watching is how shipping insurance rates adjust, and whether oil-importing nations begin to seek alternative routes or suppliers. The closure of the Strait of Hormuz is not just a regional issue; it’s a chokepoint for the entire global economy.
