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Iran Conflict 2026
21MAY

Hormuz down 70%; 150 tankers at anchor

3 min read
09:55UTC

Vessel traffic through the Strait of Hormuz has fallen 70%. Six of the world's largest shipping lines have halted transits. The waterway that carries a fifth of global traded oil is, for commercial purposes, closed.

ConflictDeveloping

Vessel traffic through the strait of Hormuz has fallen 70%. More than 150 tankers sit at anchor in open Gulf waters rather than attempting transit. CMA CGM, Maersk, Hapag-Lloyd, Nippon Yusen, Mitsui, and Kawasaki Kisen have all suspended sailings. CMA CGM imposed an emergency surcharge of $2,000–4,000 per container, effective immediately — a cost that will propagate through global supply chains within weeks.

the strait carries roughly 20% of the world's traded oil and approximately a quarter of global liquefied natural gas. Brent Crude sat at $73 before the strikes ; it opened Saturday at $82.37 (ID:108), an 11% rise driven by risk pricing rather than physical shortage. If the 70% traffic reduction holds, markets will begin pricing actual supply loss. Goldman Sachs had forecast Brent at $110; JP Morgan projected $120–130 under prolonged disruption and raised its US recession probability to 35% (ID:111). With tankers under direct fire, those figures describe a midpoint, not a ceiling.

The alternative — routing around the Cape of Good Hope — adds roughly 15 sailing days per laden tanker voyage, with proportional increases in fuel, crew, and scheduling costs. Import-dependent economies in Asia absorb the worst of this: Japan, South Korea, and India source between 60% and 80% of their crude from Gulf producers, all of it transiting Hormuz.

The global economy has not experienced a sustained physical closure of the strait in the post-globalisation era. The closest precedent — the 1984–88 Tanker War — disrupted traffic but never stopped it; the US Navy's Operation Earnest Will ensured a minimum flow of escorted tankers. Here, the US Navy is engaged in offensive operations, not convoy protection, and Gulf States that might otherwise support escort missions are themselves under bombardment — the UAE alone has absorbed 137 missiles and 209 drones (ID:97). The chokepoint the global economy treated as permanently open is, for the first time since it became the world's primary oil artery, functionally shut.

Deep Analysis

Deep Analysis
Synthesis

The 150 anchored tankers represent a stress test of the international maritime order — the system of commercial insurance, flag-state protection, and US naval deterrence that has kept Hormuz open through previous crises. If vessels at anchor begin to be targeted directly, states with commercial interests currently standing aside — Japan, South Korea, India — face direct pressure to act. The 70% traffic reduction already constitutes the strategic effect of a blockade; Iran need not close the strait completely to achieve its objectives.

Root Causes

Three forces compound simultaneously: direct Iranian attacks provide the kinetic trigger; war-risk insurance requirements amplify the effect far beyond what physical interdiction alone produces; and voluntary carrier suspensions crystallise the disruption into a structural withdrawal. The behavioural mechanism is the critical one: Iran need not sink every tanker, only enough to make operators unwilling to risk their vessels, crews, and insurability. A handful of attacks achieves a disproportionate commercial effect.

Escalation

If the US or allied navies deploy convoy escorts, the strait becomes a military operation area, raising the prospect of direct confrontation between escort vessels and Iranian naval forces. Gulf states that might otherwise support escort missions are themselves under bombardment. Oman — the traditional diplomatic back-channel — has not publicly indicated activation, and no mediator currently holds leverage over both parties.

What could happen next?
2 consequence2 risk1 meaning
  • Consequence

    With 14–15 million barrels per day of Gulf oil flows at risk, oil-importing nations in Asia and Europe face immediate supply shortfalls that strategic reserves can buffer for weeks to months but cannot replace indefinitely.

    Short term · Assessed
  • Risk

    If the remaining 30% of Hormuz traffic is deterred by further attacks, the effective closure of the strait would constitute a global economic emergency comparable in magnitude to the 1973 oil shock.

    Short term · Suggested
  • Consequence

    150 tankers at anchor represent an enormous deferred supply inventory that will create a price-suppressing glut when — and if — the strait re-opens, complicating economic recovery planning for oil-producing states.

    Medium term · Suggested
  • Risk

    Anchored vessels in open Gulf waters may themselves become targets, as the conflict has already demonstrated willingness to strike commercial shipping without apparent discrimination.

    Immediate · Suggested
  • Meaning

    The scale of voluntary commercial withdrawal signals that US naval presence in the region has failed to deter Iranian anti-shipping operations in practical terms, regardless of its continued strategic deterrent value.

    Immediate · Assessed
First Reported In

Update #7 · Hezbollah enters; tankers burn in Hormuz

gCaptain· 2 Mar 2026
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Different Perspectives
Turkey (Shakarab consideration)
Turkey (Shakarab consideration)
Ankara serves as one of two Western-adjacent Iran back-channels while Turkish national Gholamreza Khani Shakarab faces imminent execution on espionage charges in Iran. President Erdogan cannot deflect the domestic political crisis that a Turkish execution would trigger, which would force suspension of the mediating role.
Germany (Bundestag gap)
Germany (Bundestag gap)
Belgium, Germany, Australia, and France committed Hormuz coalition hardware on 18 May. Germany's Bundestag authorisation for the coalition deployment remains pending, creating a constitutional gap between the commitment announced and the parliamentary mandate required to operationalise it.
IEA and oil market analysts
IEA and oil market analysts
The IEA's $106 May Brent projection met the market in one session on 20 May as Brent fell 5.16% on diplomatic optimism. Goldman Sachs and Morgan Stanley's two-layer premium framework holds: the kinetic component compressed; the structural insurance component tied to Lloyd's ROE remains unresolved.
Hengaw
Hengaw
Documented the dual Kurdish execution at Naqadeh on 21 May, the two Iraqi-national espionage executions on 20 May, and Gholamreza Khani Shakarab's imminent execution risk. The 24-hour cluster covers two executions at one facility, the first foreign-national espionage executions, and a Turkish national whose death would suspend Ankara's mediation.
Lloyd's of London
Lloyd's of London
Hull rates stand at 110-125% of vessel value on the secondary market; the Joint War Committee has conditioned cover reopening on written ROE from the coalition or PGSA. The Majlis rial bill makes any compliant ROE structurally impossible to draft while the PGSA's yuan portal remains its operational mechanism.
United Kingdom and France (Northwood coalition)
United Kingdom and France (Northwood coalition)
The 26-nation coalition paper requires Lloyd's to see written rules of engagement before Hormuz war-risk cover reopens. The Majlis rial bill adds a second governance incompatibility on top of the unpublished PGSA fee schedule; coalition ROE cannot mention rial without conceding Iranian sovereignty over the strait.