At its narrowest point, the Strait of Hormuz is barely 33 kilometers. Because of its location in the middle of the oil-rich Middle East, the strait can disrupt global energy flow and halt economies.
After the United States and Israel launched joint strikes against Iran on February 28, Iran retaliated by effectively blockading the Strait of Hormuz in March. This move resulted in a nightmare for states heavily dependent on the Gulf States’ oil and gas. What began as a targeted military campaign to change the Iranian regime and neutralize its nuclear and missile program turned into one of the most severe energy security crises in the world.
This crisis further escalated on April 12 when, after diplomatic negotiations between the United States and Iran collapsed in Pakistan, the U.S. Navy began blockading maritime traffic entering and leaving Iranian ports. The crisis of Hormuz uncovered some uncomfortable truths about the vulnerability of a global energy structure whose routes pass through a handful of geographical chokepoints. Any pressure tactic applied near to one of these chokepoints can place global shipping lanes, international law, and geopolitical stability under simultaneous strain. The World’s Most Dangerous Bottleneck In 2025, approximately 25-30 percent of the world’s seaborne oil trade and roughly 20 percent of all Liquefied Natural Gas (LNG) transited the Strait of Hormuz. That translates to around 20 million barrels of oil and petroleum products per day, along with over 110 billion cubic meters of LNG annually. Some 93 percent of Qatar’s LNG exports and 96 percent of the UAE’s LNG exports passed through the Strait. Presently there is no cost-effective alternative. Countries such as Iran, Iraq, Kuwait, Qatar, and Bahrain rely almost exclusively on the Strait for their energy exports, unlike Saudi Arabia and the UAE , which have limited overland pipeline capacity to reroute a combined 3.5-5.5 million barrels per day from the east coast to the west.
Before the war, approximately 138 ships transited the Strait each day, according to the Joint Maritime Information Centre. Since the beginning of March, fewer than 100 vessels have made the crossing in total, with an average of just five to six per day. Most of the ships that are permitted to pass have connections to Iran itself. Several Gulf oil producers , unable to export, have been forced to cut total output by more than 11 million barrels per day as onshore and offshore storage fills.
The price increases are also staggering; before the conflict, Brent crude oil traded at $71.86 per barrel. After rising well above $100, it is currently around $98 . Oil prices have risen nearly 60 percent in just over a month. J.P. Morgan has estimated that even a moderate scenario, with Brent crude holding at $80 per barrel through mid-year, would depress global GDP growth for the first half of 2026, and it would also push global consumer price inflation above one percentage point. A prolonged crisis would be far worse. A scenario of $200 oil per barrel is not far-fetched. U.S Naval Blockade On April 12, the United States announced the start of its own naval blockade of the Strait of Hormuz where U.S forces will stop or intercept vessels coming out from Iranian ports. One week later, it did just that by seizing an Iran-flagged cargo ship. The move was made during a ceasefire agreement but after negotiations between the United States and Iran failed to conclude any deal to end the war.
According to the U.S. Central Command , more than 12 warships and 100 fighter and surveillance aircrafts are involved in this mission. It’s likely that the United States will position its naval blockade around the Gulf of Oman because anywhere near the Iranian coast will put them at risk of drone and missile attack from Iran. Up until the seizure of the Iranian cargo ship, the Central Command claimed that no ships had broken through, that ten vessels had been turned back after being directed to return to Iranian ports, and that a U.S. destroyer stopped two oil tankers near Chabahar.
However, according to Reuters , at least eight ships, including three Iran-linked tankers, were observed crossing the waterway the same day that the United States announced the blockade. These contrasting claims show that the blockade is real, but porous. Why the Blockade And Why Now? After exhausting both military and diplomatic options, the Trump administration has turned to sustained maritime pressure to achieve its aims. Regime change has not occurred, but the administration still wants to reduce Iran’s military capacity and nuclear program. To force Iran to compromise, it is attempting to reduce Iranian oil exports (which increased massively in March and April as compared to 2025) and reshape control of Strait of Hormuz. Additionally, Iran has been charging vessels up to $2 million for safe passage through the Strait, which is a significant toll on one of the world’s most critical shipping channels.
The United States has threatened to interdict not just oil tankers but any vessel paying these tolls. In doing so, the United States is trying to reframe the Strait not as a neutral international waterway but as a contested space where American strategic interests now dictate the rules of passage.
The blockade has introduced fresh uncertainty into global oil markets at a particularly sensitive moment. Even at a conservative estimate of $90 per barrel, Tehran earned nearly $5 billion from oil exports in the past month alone, roughly 40 percent more than it was earning before the war began. Now, with its ports under blockade and export routes targeted, that revenue stream faces direct disruption. The repercussions of this blockade extend beyond Iran as a prolonged blockade risks further driving up petrol and food prices globally, creating further energy shortfalls in import-dependent economies and constraining access to critical materials including aluminum, helium, and fertilizer.
Despite these concerns, the most enduring consequence of the blockade is not economic but legal. Under Article 38 of the United Nations Convention on the Law of the Sea (UNCLOS), the Strait of Hormuz is a “strait used for international navigation,” where the right of transit passage is guaranteed. By obstructing vessels in international waters, the United States is effectively asserting that national security can override this foundational treaty norm. The United States has not signed UNCLOS, but it recognizes most of it as customary international law. By departing from that custom, the United States risks setting a precedent that other powers can exploit. Any major power with naval assets can now cite American action in the Gulf as legal cover for enforcing the blockade of a sensitive chokepoint under the banner of national security.
The closure of the Strait of Hormuz has not merely disrupted energy markets. Rather, it has nullified the assumptions that the international energy system has rested on for decades. The idea that the global LNG trade created genuine supply diversification has been exposed as partly illusory, since that trade is still funneled through one narrow chokepoint. The belief that the strait was too important to be weaponized has also been refuted.
Whether this crisis escalates further, or whether back-channel diplomacy finds a quiet resolution, will shape the norms governing international waters for decades. The Strait may eventually reopen to all, as it has before. But the precedent of regional and superpower unilaterally blocking a global chokepoint, without a UN mandate, will impact the geopolitical vulnerability of other significant sea trade routes and possibly unravel decades of carefully constructed maritime law.
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