The “Friendly” Blockade: Iran’s Toll-Booth Internationalism

Iran has converted the Strait of Hormuz into a gatekeeping system based on political loyalty. If the precedent holds, the global maritime commons may not survive it.

Photo by Venti Views on Unsplash

Since mid-March 2026, the Islamic Revolutionary Guard Corps Navy has been operating a de facto checkpoint at the throat of the world’s oil supply. Vessels entering the Strait of Hormuz must submit full documentation, including ownership records, cargo manifests, and crew nationality, for geopolitical and sanctions screening. They must obtain Iranian clearance codes. Many accept escorted passage through a controlled corridor overseen by IRGC patrol boats. Traffic through the 21-mile passage has plummeted by more than 90 percent since early March, with only vetted transits from politically approved nations clearing the strait at all.

This is not a traditional blockade. It is something potentially more durable: selective interdiction, calibrated by political loyalty. Iranian Foreign Minister Abbas Araghchi has publicly confirmed that “friendly nations” including China, Russia, India, Iraq, and Pakistan receive priority or conditional passage. Vessels linked to the United States, Israel, or their close allies face delays, enhanced inspections, turn-backs, or outright prohibition. Iran’s parliament is advancing legislation to formalize the system through official tolls and fees, with payments assessed in Chinese yuan according to Lloyd’s List and Atlantic Council research. The ad hoc has become institutional.

The policy has emerged from the broader conflict that erupted on February 28, 2026, when US and Israeli strikes began targeting Iranian military infrastructure, including the assassination of Supreme Leader Ali Khamenei. Now in its fifth week, the war has not shut the strait entirely. It has done something subtler: Tehran has converted a universal transit corridor into a geopolitical sorting mechanism. That distinction is what makes this moment significant far beyond the current conflict.

The Death of the Global Blue?

For centuries, the high seas have been governed by a single revolutionary principle: the Global Blue, the idea that the oceans belong to no single nation and to all nations equally. Hugo Grotius first articulated it in Mare Liberum in 1609. It later crystallized in the 1982 UN Convention on the Law of the Sea, which holds that straits used for international navigation must remain open to all vessels regardless of flag or political alignment. The Strait of Hormuz, carrying roughly 20 percent of the world’s oil and LNG in normal times, is legally obligated to permit “transit passage” without interference.

Iran’s system directly challenges that principle. By conditioning passage on political fealty rather than legal right, Tehran asserts sovereign authority that overrides the longstanding norm of unimpeded navigation. Iran, which signed but never ratified UNCLOS, argues it is exercising authority over its territorial waters and has never fully accepted the transit passage regime. The Wikipedia entry on the crisis notes that legal analysts have described the closure as a violation of UNCLOS’s transit passage provisions. The message is unmistakable: in practice, Iran now decides who may use this gateway.

The closure has been described as the largest disruption to the energy supply since the 1970s oil crisis. The precedent it sets, that political alignment determines access to a global trade route, is dangerous and contagious in ways that extend well beyond this conflict.

The Feudalization of the High Seas

Iran is replacing the universal commons with a tiered maritime order where access depends on political loyalty. “Friendly” vessels move with relative ease, often under escorted corridors. “Unfriendly” ones face unpredictable barriers. The economic pain is uneven and deliberate.

Oil prices spiked sharply after the disruptions began. Brent crude surpassed $100 per barrel on March 8, for the first time in four years, rising to a peak of $126 per barrel. As of early April, prices are trading around $104 to $106 amid IEA emergency reserve releases and partial rerouting. Gulf producers have slashed output amid the instability. Insurance costs for non-approved vessels have become prohibitive, and the restriction of shipments by more than 90 percent has raised energy and agricultural input costs worldwide.

The tolls themselves mirror medieval toll-road logic. Payments are being assessed by the IRGC in Chinese yuan, according to Lloyd’s List and confirmed by Atlantic Council research on Iran’s payment systems. One vessel reportedly paid $2 million for a single transit. Loyalty has a literal price at Hormuz, and it is posted in the currency of Iran’s most important partner.

China’s Arbitrage

China has navigated the new system adeptly. Half of China’s oil imports and nearly a third of its LNG normally transit the Strait of Hormuz. By maintaining “friendly” status through a 25-year cooperation agreement signed in 2021, Beijing continues securing Iranian crude at discounts while publicly maintaining neutrality. China’s shadow fleet, documented in a March 31 House Select Committee report, has continued making deliveries at near pre-war levels, buying sanctioned Iranian oil at below-market rates while the rest of the world pays the spike.

The economics favor Beijing sharply. Small independent Chinese refineries have continued importing discounted Iranian crude while major state-owned enterprises maintain cleaner hands, a division of labor that insulates China’s strategic interests while channeling profit to its industrial base. The arrangement also advances a longer-term Beijing objective: settling oil transactions in yuan rather than dollars, which reduces exposure to US sanctions leverage and advances the internationalization of the renminbi. Iran’s crisis has become China’s laboratory.

Even China’s position is not entirely secure. On March 27, Iran turned back two Chinese ships attempting to enter the strait over alleged documentation violations, a reminder that Tehran’s vetting system reserves the right to discipline even its partners. Friendship, in the new maritime order, is conditional.

India’s Dilemma: The Price of Non-Alignment

India occupies a more precarious position. Diplomatically entangled with both Washington and Tehran, it has been designated “conditionally friendly” and granted passage for select Indian-flagged vessels, including LPG tankers bound for western Indian ports. But the treatment remains subject to periodic review. The message is clear: neutrality is not a protected category. It is an unstable middle ground that can be revoked.

India’s predicament exposes the ideological core of Iran’s system. Non-alignment, once a proud doctrine of post-colonial states, is now a precarious balancing act. The Hormuz regime does not reward independence. It demands explicit loyalty. The “conditional” category is a gilded cage, permission to pass that can be withdrawn at any time, for any reason Tehran chooses to articulate. Indian officials have dismissed reports of tolls as “baseless”, citing international law. The legal point may be valid. The geopolitical reality is harder to argue away.

The South China Sea Precedent

If Iran can reclassify an international strait as a sovereign toll road based on political preference, the template is available to any regional power with sufficient military presence and will.

China, which claims “indisputable sovereignty” over the South China Sea and has built militarized artificial islands throughout it, is the obvious candidate. Under UNCLOS, these features do not generate territorial waters. But China relies on seaborne imports for over 63 percent of its oil needs, half of which flow through Hormuz. Having watched US naval operations in real time during this conflict, and having seen the template Iran has constructed, Beijing now possesses both a model and an incentive. A “friendly nation” clearance requirement applied to the South China Sea, the Malacca Strait, or Bab el-Mandeb would follow the same logic.

The danger is cumulative. Every maritime chokepoint controlled by a regional power becomes a candidate for the same treatment once the norm of unconditional transit passage cracks at Hormuz. Bruegel’s analysis of China’s strategic calculus notes that a protracted conflict over Iran would divert US military resources away from the Indo-Pacific—a consequence Beijing is observing closely and without apparent displeasure.

Legal Vacuum

The legal architecture designed to prevent this is paralyzed. UNCLOS has no enforcement mechanism; it relies on state compliance. The International Tribunal for the Law of the Sea cannot compel a non-signatory and lacks coercive power even against signatories. The UN Security Council, where China and Russia hold vetoes, will not pass resolutions condemning Iran’s closure, as Bahrain’s April 2 resolution authorizing military force to reopen the strait met immediate opposition from both. Both powers see in the Hormuz precedent a template for their own regional ambitions.

Iran’s non-ratification of UNCLOS gives it additional maneuvering room. Tehran can claim it never accepted the transit passage regime and is merely exercising sovereignty it never ceded. China, by contrast, is a UNCLOS party. If Beijing adopts a similar policy while bound by the convention, the breach would be unambiguous, and a genuine test of the legal order’s vitality would finally arrive.

The United States, engaged in an active shooting war with Iran and facing severe domestic political constraints, cannot project credible naval force to enforce freedom of navigation without risking further escalation. A UN task force to ease humanitarian flows has been discussed. Progress has been minimal. Iran has correctly calculated that the costs of defiance are lower than the costs of compliance.

New Maritime Feudalism

What is unfolding in the Strait of Hormuz is more than a wartime tactic. Even if the broader conflict resolves, the system Iran has constructed demonstrates that a major chokepoint can be unilaterally re-regulated without prohibitive consequence. That demonstration is itself the damage.

Freedom of navigation was never just about shipping. It was the physical infrastructure of globalization, the assumption that made dispersed supply chains possible across contested seas. When that infrastructure becomes subject to political veto, the architecture of interconnectedness begins to crack. The disruption has already been called the largest to global energy supply since the 1970s crisis, with effects on oil, LNG, fertilizer, and aluminum markets worldwide.

The response, if one comes, cannot be merely rhetorical. Reasserting naval escorts carries escalation risk in a live conflict. Accelerating alternative pipelines and overland routes requires investment and political will that have been in short supply. Meanwhile, the economic burden falls hardest on those least aligned with the gatekeeper, a punishment for political independence that compounds over time.

The Strait of Hormuz was once a symbol of the world’s interconnected prosperity. Under the IRGC-managed regime, it has become a symbol of that world’s fragmentation. The seas are no longer reliably free. In practice, they are increasingly for sale, or denied, to those who fail the political test.