The first transmission channel is crude. Once the fighting began, insurers, shipowners and traders started pricing the risk that tanks, tankers and terminals could be disrupted, even if the strait never fully shuts. That is enough to move markets fast.

The second channel is freight. The U.K. Maritime Trade Operations Centre reported 10 attacks on ships as of March 8, the CRS said in March, while ocean carriers have been diverting away from the Red Sea and Suez Canal route and sailing around the tip of South Africa instead. That adds days to voyages and pushes up fuel burn and charter costs.

War-risk insurance has become another tax on trade. Policies in the region reportedly carry 72-hour cancellation clauses, and premiums have risen to four or five times their previous level, the CRS reported in March. The math is simple enough: when a voyage gets pricier, someone eventually eats the bill, and it is usually the importer.

The strait itself is not functioning like a cleanly sealed gate. Beginning on March 4, Iranian forces declared it “closed,” threatening and carrying out attacks on ships attempting to transit the Strait, the CRS said in March. Even so, vessels carrying Iranian oil continued to move through the strait into early March, with one industry analysis firm estimating Iran’s exports averaged 2.1 million barrels a day in that period, the CRS noted in March.

That uneasy combination, partial flow, rising risk, higher costs, is what makes the shock harder to dismiss. It is less a blockade than a toll road with artillery on the shoulder.

The IMF’s read on the conflict is blunt: the war in the Middle East has disrupted oil and gas flows and darkened the global economic outlook, the Fund wrote last month. Countries able to export oil and gas undisturbed face the smallest headwinds. Net importers, especially those where energy imports loom large as a share of GDP, are in the worst spot.

How severe that burden becomes depends critically on policy space, proxied by sovereign credit ratings, the IMF said last month. Translation: the richer the policy buffer, the easier it is to subsidize fuel, defend a currency or borrow through the shock. The poorer the buffer, the faster the pain gets passed along.

That leaves several familiar pressure points. The net oil importers in that bottom-left quadrant of vulnerability, with the least room to maneuver, were central to discussions at the Spring Meetings last week, the IMF said last month. Europe and industrial Asia are also exposed through gas prices, which rose almost 63% and 54% respectively in the week before operations began, the CRS reported in March.

Those are not abstract market moves. They hit household heating bills, factory input costs and current accounts all at once. Energy shocks have a habit of doing their work twice, first at the pump and then in the rest of the economy.

The reach of the disruption goes well beyond benchmark crude. Approximately 25% of the world’s LNG exports need to transit the Strait, mainly from Qatar and the United Arab Emirates, the CRS found in March. Most Qatari exports are destined for Asian markets, including China at 24%, the CRS found in March.

That matters because LNG is not just a power-sector fuel. It is a feedstock, a heating source and, in some markets, a backup for a grid that does not have many spare gears left.

The Gulf also sits inside the fertilizer supply chain. Iran, Saudi Arabia, Qatar, the UAE and Bahrain account for over a third of global urea supplies, the CRS reported in March. Iran, Oman, Qatar and Saudi Arabia produced about 9% of total ammonia supply in 2025, while Iran, Kuwait, Qatar, Saudi Arabia and the UAE produced almost a quarter of the world’s supply of sulfur in 2025, the CRS said in March.

Urea, ammonia and sulfur feed fertilizer production. If those flows stay tight, the cost pressure can travel from Hormuz to farms and then, eventually, to food prices. It is a slower-moving shock than oil, but not a smaller one.

Helium is another quiet vulnerability. The region accounts for roughly 30% of global helium production capacity, most of it produced as a byproduct of natural gas processing, the CRS found in March. That does not sound dramatic until a hospital, chipmaker or aerospace supplier is short of an input it cannot easily replace.

Governments have not been sitting still. On March 3, President Trump said he had ordered the U.S. International Development Finance Corporation to provide political risk insurance and guarantees for maritime trade, especially energy moving through the Gulf, the CRS reported in March. The DFC later said it was ready to support trade through its insurance and loan guarantee products, and announced a reinsurance facility to insure losses up to approximately $20 billion on a rolling basis for qualifying vessels, the CRS said in March.

The IEA has another buffer, but it is not bottomless. Government-controlled oil stocks among IEA members were more than 1.2 billion barrels at the end of the fourth quarter of 2025, including about 415 million barrels in the US Strategic Petroleum Reserve, the CRS reported in March. The IEA estimates those stocks could be drawn down at up to 25 million barrels a day for about two months, with emergency stocks potentially exhausted in roughly six months, the CRS said in March.

That is a cushion, not a cure. The IMF has argued that stronger global cooperation is needed to contain the damage, the Fund wrote last month. For now, the question is not whether the shock is real. It is how long the world can keep paying for it before higher energy prices, rerouted shipping and tighter insurance begin to bite harder in the global economic outlook.