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Iran Conflict 2026
20APR

Hormuz down 70%; 150 tankers at anchor

3 min read
10:10UTC

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 , 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% . 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 . 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
Israel
Israel
The IDF struck a Lebanese army unit on 6 June, killing a colonel, and privately told Moscow that shelling near Bushehr was accidental, per Putin's SPIEF disclosure. Israel is advancing in Lebanon past an unenforced ceasefire text while maintaining a back-channel to Russia on nuclear-site deconfliction.
Lebanon
Lebanon
President Aoun told CNN on 5 June that Iran uses Lebanon as a bargaining chip and urged Hezbollah toward diplomacy; on 6 June an IDF strike killed a Lebanese army colonel on the Khardali-Nabatieh road. The Lebanese state is publicly rejecting Iranian tutelage while the army sustains casualties from Israeli fire and the Washington framework remains unenforced.
Bahrain
Bahrain
Bahrain's US Fifth Fleet headquarters was among the targets in the 5-6 June two-country salvo; its PAC-3 magazine stands at 87 per cent depletion with an 18-month resupply gap and no comparable arms sale has been announced. The state is defending a critical US regional command on a thinning interceptor stock.
Kuwait
Kuwait
Kuwait received a $1.98bn US counter-drone sale approval on the same day IRGC missiles targeted its bases; it expelled two Iranian diplomats on 4 June and filed a formal protest. The arms approval gives Kuwait a future capability but leaves a 6-18 month delivery gap that the salvo tempo is already pressing.
Russia
Russia
Putin reaffirmed Russia's offer to hold Iran's 440.9 kg HEU at SPIEF on 6 June, said Russia is not arming Iran, and disclosed that both the US and Israel privately told Moscow that shelling near Bushehr was accidental. The restatement casts Moscow as the only remaining mediator both sides call, a position serving Russian interests whatever the nuclear file produces.
Iran
Iran
The IRGC, per Iranian state media, fired seven ballistic missiles at US bases in Kuwait and Bahrain, the largest two-country salvo of the war, and framed the launches as lawful retaliation; Foreign Minister Araghchi rejected Aoun's bargaining-chip accusation and Velayati warned Beirut against diplomatic naivety. Tehran has sent no HEU counter-proposal since Araghchi confirmed no progress on 4 June.