A president who launched a war to protect American interests has watched it choke the one supply line his allies built to survive that war.

"If something like that happens, we'll take care of it. We've done that with the Houthis before."

— Donald Trump, July 21, 2026

On Thursday morning, Brent crude breached $100 a barrel for the first time since May. The trigger was not a new battle or an unexpected airstrike. It was two Saudi oil tankers that the Houthis said they hit in the Red Sea, carrying crude from Yanbu port through the Bab el-Mandeb Strait.

The strait is the last remaining maritime artery for Saudi oil exports. When the United States and Israel launched their war on Iran at the end of February, Iran responded by closing the Strait of Hormuz. Saudi Arabia scrambled to move its production westward: the East-West Pipeline (Petroline) carries crude from the eastern fields across the desert to the Red Sea port of Yanbu, from where tankers thread through Bab el-Mandeb to Asian markets.

As of late July, those Yanbu shipments averaged four million barrels per day, up from roughly one million a year earlier. In total, petroleum volumes transiting the Bab el-Mandeb reached 7.4 million barrels per day in June, about seven percent of global output. The Houthis announced a complete maritime blockade on Monday. By Thursday, they said they were enforcing it.

Translation: the world's second-largest oil exporter just lost the one exit ramp that kept it off the map this spring.

The timeline matters. For months, the war has played out across a single chokepoint. The Strait of Hormuz handles roughly 20 percent of global oil supply. Iran's closure sent Brent to $126 in March. It settled back to a range between $80 and $90 as the world adapted: rerouting, consuming reserves, absorbing pain. The adaptation always involved the Bab el-Mandeb, the 18-mile-wide strait between Yemen and the Horn of Africa that connects the Red Sea to the Gulf of Aden.

Saudi Arabia spent hundreds of millions upgrading its pipeline infrastructure to make that alternative route viable. China, South Korea, Japan, and India adjusted their import patterns. Shipping companies built the extra leg into their schedules.

Then the Houthis declared they would replicate the Hormuz playbook on the western flank.

"We call upon the people of our great nation to continue the general mobilisation," the Houthi leadership said in a statement. "We affirm the right of our great people to respond to the blockade with a blockade, and to all escalation with escalation."

The stated trigger was last week's bombing of Sanaa Airport, which the Houthis blamed on Saudi forces. The internationally recognized Yemeni government in Aden claimed responsibility instead, saying it was targeting an Iranian aircraft. Both sides of that dispute are, technically, fighting each other. The Houthis also fired ballistic missiles at Abha International Airport in Saudi Arabia. The Saudi-led coalition said it intercepted them.

Either way, the truce that held Hodeidah and the Red Sea coast in a fragile peace for four years is broken.

The economic mechanics are brutal. Nada Sanders, a distinguished professor of supply chain management at Northeastern University, called the simultaneous closure of both straits a "correlated global supply chain crisis." Hormuz is primarily an energy shock. Bab el-Mandeb is broader: 15 percent of global maritime commerce and 30 percent of container traffic move through it. Electronics, automotive parts, machinery, food, fertilizer. The alternative route around Africa adds more than 10 days to most voyages.

"In 2024, about 4.1 billion barrels of crude and refined products passed through the strait," Sanders wrote. "A blockade there is not just an energy event. It is a logistics event."

The Houthis demonstrated the ability to enforce such a blockade years ago. Between late 2023 and late 2025, they disrupted Red Sea shipping at scale in response to Israel's war on Gaza, forcing global reroutes that cost the shipping industry billions. The attacks ended with the Gaza ceasefire in October 2025. Now the Houthis have reactivated that capability, and the global economy is far less resilient than it was two years ago.

Inside the United States, the reserves are hollow. The Strategic Petroleum Reserve shed 5.1 million barrels in the week ending July 17, dropping to 311.4 million barrels: the lowest level since March 1983. The government has been lending out 172 million barrels since March under an International Energy Agency coordination, with companies expected to repay the crude at premiums between 18 and 28 percent. More than 133 million barrels have been contracted out so far.

A Government Accountability Office report released in early July found the SPR's operational capability is compromised. The reserve can draw down oil at only 61 percent of its originally intended rate. Its capacity to accept returning crude has slipped to 56 percent of design specifications. The $1.4 billion, decade-long Life Extension Phase 2 overhaul has repeatedly missed its schedule and shrunk in scope.

"When commercial and SPR holdings are combined, total U.S. crude inventories stood at 726.2 million barrels as of July 10, down 129 million barrels and the lightest since 1984," Reuters reported.

The average U.S. gasoline price rose to $4.09 on Thursday.

Translation: the nation's emergency oil cushion has been draining for five months, the pumps that are supposed to refill it are broken, and the thing the cushion was meant to protect against is actively getting worse.

Trump's response followed a familiar pattern. When asked about the Houthi blockade threat on Tuesday, the president said the United States "will just have to take care of business." He noted that the U.S. had "done that with the Houthis before" and said he had not "heard from them in a while," as if the three years of Red Sea attacks between 2023 and 2025 were a minor footnote.

On Thursday, after the Houthis claimed strikes on the two tankers, Trump said he would hold Iran responsible.

Reuters noted that a new Red Sea front would challenge an already stretched U.S. military, which is conducting sustained air campaigns over Iran while managing the Hormuz closure's fallout. The Pentagon has been reluctant to disclose the full scope of its forces committed to both theaters.

Juliette Kayyem, a former Obama administration official and senior lecturer at Harvard's Kennedy School, wrote that the war's trajectory exposes a fundamental miscalculation. "A bunch of military analysts assured the American public that our air dominance was unparalleled," she wrote. "The 'never right but always certain' crowd didn't realize the war was going to be fought on water."

University of Chicago political scientist Robert Pape compared the situation to a ship striking an iceberg. "The Titanic is now hitting the iceberg," he said. "There are not enough lifeboats for the world economy."

The image is apt. The United States launched this war with the assumption that its military superiority would compress the timeline and contain the collateral damage. Five months in, Iran has closed a strait. Its allies in Yemen have closed the alternative. Saudi oil is stranded. The SPR is at a 43-year low. Gas prices are back above $4. And the president's reassurance is that the United States has handled the Houthis before, as if the previous handling amounted to anything more than paying shipping companies to reroute around Africa.

The Houthis do not need to sink every ship in the Bab el-Mandeb. They need to make enough insurance companies nervous that commercial vessels stop transiting. Stephen Flynn of Northeastern's Global Resilience Institute called this "the asymmetry of chokepoint warfare": the blockade enforcer does not bear the economic cost of the disruption. The rest of the world does.

Oil topped $100 on Thursday. The question is whether it stops there.

The war was sold as a precision strike against a rogue regime. It turned into a global siege of the energy markets, carried out by adversaries who needed nothing more than a handful of drones and the patience to wait while an empire outspent its own reserves.