Strait of Hormuz Shipping Risk Scenarios: What Changes First During Escalation

Overview

The Strait of Hormuz is a narrow waterway between Iran and Oman where the shipping lanes compress to just two miles wide in each direction. Every day, roughly one-third of all seaborne-traded oil and a quarter of global liquefied natural gas (LNG) transits this corridor. When military escalation raises the possibility of disruption, the consequences ripple through shipping insurance markets, tanker routing decisions, and energy supply chains within hours -- well before any physical blockade occurs.

This article maps out three escalation scenarios for shipping risk in the Strait: a harassment campaign using IRGC fast-attack boats and drones that raises costs without closing the waterway; a partial denial operation using mines and coastal anti-ship missiles that forces convoy-style transits under naval escort; and a full closure attempt that would require international mine-clearing operations lasting weeks or months. Each scenario carries different implications for insurance premiums, delivery timelines, LNG spot prices, and the viability of alternative pipeline routes.

The scenarios are grounded in Iran's demonstrated naval capabilities, MARAD and Lloyd's List advisories issued since strikes began, and historical precedents from the 1980s Tanker War when Iran mined the Strait and attacked commercial shipping during the Iran-Iraq War.

What We Know

As of February 28, 2026, coverage on strait of hormuz shipping risk should prioritize primary documentation and high-credibility reporting. This section focuses on confirmed information and labels uncertainty directly.

• Current reporting on strait of hormuz shipping risk should prioritize named institutional sources and date-labeled updates. EIA oil chokepoints
• Technical and legal claims are strongest when primary documents and independent reporting align. MARAD alert 2025-003A
• Where verification is incomplete, this page labels uncertainty instead of implying certainty. FAA restrictions and notices
• Forward-looking sections are conditional and evidence-based, not predictive claims. EASA CZIB update
• Internal links connect this page to timeline and hub coverage for continuity. World Bank commodity outlook (Oct 2025)

Analysis

Scenario 1: Harassment campaign (high probability, moderate impact)

In this scenario, IRGC Navy fast-attack craft and drone units conduct close approaches, warning shots, or limited strikes against commercial vessels without attempting to fully close the Strait. Iran employed this tactic repeatedly between 2019 and 2024, seizing or harassing tankers in the Gulf of Oman. The operational effect is not physical closure but cost inflation: war-risk insurance premiums climb, shipping companies reroute vessels or demand risk bonuses, and delivery schedules stretch. During the 2019 tanker attacks, premiums for a single transit jumped from around $10,000 to over $500,000 within days. A sustained harassment campaign could keep premiums elevated for months, adding $1-4 per barrel in effective transport costs.

Scenario 2: Partial denial with mines and anti-ship missiles (moderate probability, high impact)

Iran maintains an estimated stockpile of over 2,000 naval mines, including modern influence mines that are difficult to detect and sweep. Deploying even a few dozen mines in the shipping lanes would force tankers to halt transits until multinational mine-clearing operations could verify safe passage. During the 1980s Tanker War, a single Iranian mine struck the USS Samuel B. Roberts and nearly sank it. Mine clearance in the Strait's shipping lanes could take 2-6 weeks depending on density and type. Iran's coastal Noor and Qader anti-ship cruise missiles (range 120-200 km) provide a layered denial capability that forces naval escorts to operate under threat. In this scenario, traffic through the Strait drops dramatically and LNG spot prices in Asia could spike 40-80% as cargoes from Qatar are delayed or rerouted.

Scenario 3: Full closure attempt (low probability, extreme impact)

A full closure would require Iran to sustain mine-laying, anti-ship missile fire, and fast-attack operations against both commercial and naval vessels simultaneously. This is the highest-risk scenario for Iran because it would almost certainly trigger direct US and allied naval response, including strikes on Iran's coastal missile batteries and naval bases. The 1988 Operation Praying Mantis, in which the US Navy destroyed half of Iran's operational fleet in a single day, demonstrates the vulnerability of Iran's surface forces. However, even a brief 1-2 week full closure would remove roughly 17-20 million barrels per day from seaborne markets, an unprecedented supply shock that no combination of strategic reserves and pipeline alternatives could offset. Brent crude could exceed $150/barrel in this scenario. The bypass pipelines (Saudi East-West and UAE Habshan-Fujairah) have a combined capacity of about 6.5 million barrels per day, leaving a gap of over 10 million barrels per day.

What's Next

The following indicators will signal which scenario is unfolding and how shipping risk is evolving in real time.

• Monitor MARAD advisory updates and Lloyd's Joint War Committee listed-area designations for the Persian Gulf and Gulf of Oman, which directly trigger insurance premium changes and tanker routing decisions. EIA oil chokepoints
• Track AIS (Automatic Identification System) data for tanker traffic density in the Strait -- a sharp drop in transits signals that operators are self-sanctioning the route before any physical blockade, as occurred during the 2019 tanker crisis. MARAD alert 2025-003A
• Watch for US Fifth Fleet or multinational naval task force announcements of convoy escort operations, which would indicate the threat level has moved beyond harassment into active denial. FAA restrictions and notices
• Follow Asian LNG spot prices (JKM benchmark) for divergence from European prices, which would indicate that Qatar-origin cargoes are being disrupted or rerouted around the Cape of Good Hope, adding 15-20 days to delivery. EASA CZIB update

Why It Matters

The Strait of Hormuz is the single point of failure in global energy logistics. No other chokepoint handles a comparable volume of oil and LNG, and no combination of pipelines, alternative routes, or strategic reserves can fully replace it if transit is disrupted for more than a few days. Japan, South Korea, India, and China receive the majority of their crude oil imports through this corridor, meaning a sustained disruption would create economic crises across the world's largest economies simultaneously.

Shipping risk in the Strait matters beyond energy markets because it tests the credibility of freedom-of-navigation guarantees that underpin global trade. If commercial vessels cannot transit the Strait safely, insurers withdraw coverage, operators reroute, and the cost of goods transported by sea rises worldwide. Container shipping rates, bulk commodity prices, and food import costs are all affected when the maritime insurance market prices in conflict risk at a major chokepoint.

For the military dimension, the Strait is where Iran holds asymmetric leverage against vastly superior conventional forces. Even without the ability to win a naval battle, Iran can impose costs through mines, missiles, and harassment that make commercial transit economically unviable. Understanding these scenarios helps governments, shipping companies, and energy traders prepare for a range of outcomes rather than being surprised by escalation patterns that have clear historical precedents from the 1980s Tanker War.

Related Coverage

• Oil Price Shock After Iran Strikes: The Mechanics Behind It
• Iran Shadow Fleet Sanctions: How Enforcement Works
• Flight Routes and Conflict Zones: Middle East Airspace
• US Strikes Iran: Full Timeline, Targets, and Global Impact
• Iran Missile Range Map: What the Ranges Mean

Sources

Last updated: February 28, 2026. This article is revised when new evidence materially changes what can be stated with confidence.