The US military announced Monday that it has begun blocking all ships entering or leaving Iranian ports, marking a major escalation of the US war against Iran and the effective abrogation by the United States of the ceasefire announced six days earlier by Pakistani Prime Minister Shehbaz Sharif.
US President Donald Trump declared on Truth Social on Sunday that the Navy would “begin the process of BLOCKADING any and all Ships trying to enter, or leave, the Strait of Hormuz.” Two guided-missile destroyers entered the Strait on Saturday, and the Wall Street Journal reported that 15 US warships are now deployed to enforce the blockade.
The blockade is an act of war and an act of international piracy. The World Socialist Web Site condemns this criminal action, directed against Iran and against the working class of the entire world, which will pay the price in soaring energy costs, food shortages and the ever-present danger of a wider military conflagration.
The ceasefire has proven to be an opportunity, using Trump’s own phrase, to “reload” for the next phase of the war. Every ceasefire Trump has announced in the Middle East—from Gaza in January 2025, to Iran in June 2025, to the April 7 Iran ceasefire followed hours later by Israel’s strike on central Beirut that killed more than 250 people—has been a pause to regroup for the next attack.
Control of the Strait of Hormuz—and with it the oil production and distribution of Iran and the Persian Gulf region as a whole—has been a central strategic aim of the war from the outset.
Since the war began, shipping through the Strait has collapsed. Transit volumes have fallen more than 90 percent from prewar levels. What traffic remains has been dominated by Iran’s shadow fleet and Greek-affiliated tankers carrying crude to China, Iran’s largest customer, which takes 80 to 90 percent of its oil exports. Iran has continued to allow passage to ships bound for its aligned trading partners, above all, China.
Any ship that now attempts to cross into the Strait to reach an Iranian port does so without American permission, opening up the possibility of a physical attack against any country whose ships trade with Iran. Chinese Defense Minister Dong Jun stated Monday: “Our ships are moving in and out of the waters of the Strait of Hormuz. We have trade and energy agreements with Iran. We will respect and honour them and expect others not to meddle in our affairs.”
The blockade of the Strait of Hormuz is, in practice, an act of economic warfare against China as much as against Iran. Nearly half of China’s oil and more than a third of its liquefied natural gas flow through the Strait of Hormuz. The blockade places America’s hand on the energy supply of its principal rival, and on that of its “allies”—Japan, South Korea and the states of the European Union, which depend on the same flows.
Trump hinted at the thinking of US military strategists at a press briefing Monday: “We don’t need this trade. We have our own oil, gas, much more than we need. … So we don’t need it, but the world needs it, and many ships are heading to our country right now, as we speak, to load up.”
The blockade is part of a broader US campaign to seize the world’s strategic chokepoints—the Strait of Hormuz, the Panama Canal, the approaches to Greenland. American imperialism, in long-term economic decline, is attempting to offset that decline through military domination of global trade routes, securing the world’s waterways and raw materials for itself and denying them to its rivals, above all China.
In December 2025, US forces seized a China-bound oil tanker carrying 1.8 million barrels of Venezuelan crude off the coast of Venezuela. The Hormuz blockade extends that precedent to the Persian Gulf and raises the direct danger of military confrontation with China if US warships attempt to turn around Chinese-bound tankers.
The economic consequences of American imperialism’s criminal war against Iran are already catastrophic. Even before the blockade, the substantial cutting off of transit through the Strait of Hormuz has generated what the International Energy Agency has called this the worst oil crisis in history, surpassing 1979. Oil is above $100 a barrel, gasoline stands at $4.13 a gallon nationally, and more than 600 ships remain trapped in the Gulf. Goldman Sachs has raised the probability of a US recession to 30 percent.
A third of global fertilizer supply normally passes through the Strait. The war has not only disrupted immediate trade but will have a severe impact on next season’s crop yields—smaller harvests across Africa, South Asia and Latin America, food price shocks reaching countries with no direct stake in the Gulf. Hundreds of millions face food insecurity, and tens of millions could die. Global famine is a real possibility.
Within its plan for world domination, the actual conduct of the war has been characterized by increasingly desperate improvisation. On February 28, the United States launched the war and killed Supreme Leader Ali Khamenei and dozens of senior Iranian officials. Trump called on Iranians to rise against their government, and they did not. The bombing campaign that followed destroyed Iran’s telecommunications and leveled districts of its cities, but Iran did not surrender. Further assassinations of Iranian leaders through March did not bring the government down. The blockade is the next step.
US warships are now operating at close range inside a waterway 21 miles wide at its narrowest point, flanked by Iranian missile batteries, coastal defenses and thousands of naval mines. Trump said Monday that any Iranian ships approaching the blockade would be “immediately eliminated.”
The loss of a destroyer or a mass casualty event would intensify demands within the US political establishment for a ground invasion, including the seizure of Kharg Island, through which 90 percent of Iran’s oil exports are processed. Marines and troops from the 82nd Airborne Division are already deployed, and more than 50,000 US service members are in the theater. Thirteen US service members have been killed since February 28.
The Trump regime is proceeding with staggering recklessness. He has said openly that the United States will take Iran’s oil—a declaration of plunder that past administrations would have disguised behind the language of sanctions and international law. The methods of the criminal underworld are now official state policy.
The political establishment objects to none of this in principle. The New York Times editorial board called Trump’s conduct “glaring incompetence” and urged him to “involve Congress and seek help from America’s allies”—a call for bipartisan collaboration in the prosecution of the next stage of the war. The Wall Street Journal called Trump’s victory declaration premature and warned that “the job is far from finished.”
Democratic Party Senator Tim Kaine told ABC Sunday that Iran is “a regional threat” and that “we need to make sure that Iran doesn’t get a nuclear weapon.” When Trump announced the “ceasefire” a week ago, the Democrats rushed to criticize it on the basis that it left control of the Strait of Hormuz in Iran’s hands. The Democrats accept the strategic objectives and object only to the execution.
If every wing of the American political establishment endorses the war, opposition to it can come only from outside the establishment altogether. The working class must oppose the blockade and the war as a whole through its own independent political mobilization. The war is being paid for through a historic assault on the social programs working people depend on to live. At a White House lunch on April 1, Trump said the government cannot afford Medicare, Medicaid and other social programs because it is fighting wars.
The same class being asked to pay for the war in cuts to essential programs is the one being called on to fight it. Automatic draft registration for all men aged 18 to 26 takes effect in December 2026, signed into law by Trump as part of the 2026 National Defense Authorization Act. The children of steelworkers and warehouse workers, of miners and migrant farmhands, will be sent to die on the destroyers and on the beaches of the Persian Gulf—to secure China’s energy supply for American imperialism.
The fight against the war is inseparable from the fight against the destruction of social programs, the drive toward conscription and the establishment of a military-police dictatorship. The fight to defend jobs, wages and living standards must be united with the struggle against imperialist war and against the root cause of these social maladies: the capitalist system.