A FAILED CEASEFIRE? ON THE AMERICAN NAVAL BLOCKADE OF IRAN

WHAT HAS HAPPENED?

At 10 a.m. on 13th April 2026, US moved in to block the Iranian ports, a critical maritime chokepoint, after failed talks with Iran to open the trade route for the US. The blockade went into effect on 15th April 2026. The blockade is applicable to all ships, without any distinction, that engage with Iranian ports and terminals, including the Gulf of Oman. As of 19th April, the entirety of the Iranian coastline remains blocked. The move to reassert control occurred only hours after Iran had temporarily reopened the strait, following a 10-day ceasefire between Israel and Lebanon.

WHAT IS A NAVAL BLOCKADE? 

A blockade, in simple English, refers to  a strategic military and economic tool used to restrict maritime access to a coastline or region, usually disrupting entry to or departure from that region. According to the US Navy Commander's Handbook on Naval Operations Law 2022, a blockade has been defined as a “belligerent operation to prevent vessels and/or aircraft of all states, enemy and neutral, from entering or exiting specified ports, airfields, or coastal areas belonging to, occupied by, or under the control of an enemy state”. 

To implement the naval blockade, the U.S. Navy can use shipboard position beacons, satellites, planes, radar, drones and helicopters to locate and watch vessels coming in and out of the Strait of Hormuz. 

Historically, however, naval blockades have not been the most successful tactics. The most popular example in history, of how hard it is to implement blockades, is that of the Napoleonic wars fought in the 19th century. Napoleon wanted to control England, just as he had subdued other European countries. He implemented the ‘Continental System’ which essentially tried to choke off British commerce by closing the Continent to its ships and goods. The tactic backfired, and lead to smuggling of British goods into other European countries.

Interestingly, the European countries at the time had only begrudgingly agreed to implementing the blockade when Napoleon had exerted pressure. This in turn also weakened the French influence over the countries. This is quite similar to how the US allies seem to be averse in joining the naval blockade, with the UK explicitly stating that it will not be joining the American blockade.

Another historical example is that of the German U-boat campaign against Britain in the 1940s during the Second World War. As an island nation, Britain relied on merchant ships for crucial supplies, almost all of which had to pass through the Atlantic. The German Navy understood that breaking this chain had the potential to cripple Britain and their war effort. Though initially effective, the tactic was later countered by the British using the ‘convoy system’ which was the practice of grouping merchant ships together in organized formations, escorted by warships, rather than letting them sail individually across the Atlantic.

In contrast, however, there have been examples of successful blockades as well. For instance, the WWI Allied Blockade of Germany (1914–1918) wherein Britain implemented a naval blockade against Germany by restricting two critical chokepoints. These were the Dover Strait in the south (the narrow English Channel between England and France) and the Northern Patrol gap between Shetland and Norway in the north. This led to a devastating impact on Germany, with a major blow to their food supply.  

WHY DID THE US IMPLEMENT A NAVAL BLOCKADE?

Iran and the US had reached a tenuous two-week truce prior to the blockade, on 7 April 2026. Iran was slated to open the Strait of Hormuz for the US. However, Iran has accused the US of violating the terms of the ceasefire since the bombing in Lebanon, carried out by Israel, did not cease. This was an integral part of the ceasefire agreement which required the fighting to stop on all regional fronts which included Lebanon. Thus, Israel's persistent bombing and subsequent ground invasion of Lebanon, has led to destruction of more than 1400 buildings Lebanon since March 2026 and Israel is planning to further its ground invasion to seize the entire south area of the Litani river and tear down Hezbollah's presence in the country. Israel claimed that the buildings were being used to store weapons by Hezbollah. 

WHAT ARE THE IMPLICATIONS OF THE NAVAL BLOCKADE ?

Iran already suffers from the crushing weight of sanctions, and even though it has been able to function under such sanctions, the blockade could further cause the already vulnerable economy to deteriorate. For countries dependent on crude oil and gas coming from West Asia, this blockade could be a grave problem. The blockade essentially disrupts the supply of 2 million barrels of Iranian oil per day.

Previously, Iran allowed countries it deemed friendly to pass through. The countries included India, China, Japan, Turkiye and Pakistan, which were allowed to pass through the strait. Some paid tolls to Iran, which collected these in Chinese Yuan, instead of the American Dollar. Countries dependent on the imports from Iran and West Asia, especially Asian nations, will most likely bear the brunt if the blockade is not resolved soon. For instance, before the war ensured, China was a major importer of Iranian oil. Thus, it can be observed that 20% of the world’s oil, which is shipped through the Strait of Hormuz, flows to Asia, which means that the nations are extremely vulnerable to oil shocks originating from this region.

THE LOOMING THREAT OF WAR

Analysts suggest that there are only two outcomes that the blockade will result in. First will result in inflationary prices before a mutual agreement is reached. For instance, the average price of one gallon (2.8 litres) of petrol in the US currently is more than $4.12. Before the war began, the price used to be less than $3. Second, and the more concerning scenario, is if the ceasefire doesn’t hold and West Asia is engulfed in a full-scale war. 

The latter scenario is especially scarier because of the prolonged impact of the energy shortage, which will have grave aftermath on the result of the world.

In the early hours of 20th April, the US President Trump claims that the US has seized an Iranian cargo ship. While news from Iran has made it clear that no ship shall be allowed to pass through the Hormuz under any circumstances. Tensions between the nations keep rising, with no certain resolution in sight. An American naval blockade, coupled with Iran's growing agitation and consequent tightening grip over the Strait does not bode well for the world. 

In a world where every region impacts another, the impact of the rising tensions in West Asia is certain to be felt across the globe. Whether the strait holds or falls remains to be seen but the ripple effects will unquestionably reach far beyond the vessels that pass through it.