UPDATE — this extends our earlier coverage: The Gulf offramp is gone: US strikes hit a 13th night as oil breaks $100

The United States military said it disabled a tanker in the Strait of Hormuz, according to the BBC. The vessel was trying to evade a US blockade of Iranian ports.

Saudi Arabia struck targets in Yemen, and the Houthis vowed retaliation, The Guardian reported. The Houthis said they hit Saudi Arabia in response, according to Dawn.

Why it matters

The moves push the war into the world's most important oil passage. The Strait of Hormuz carries roughly a fifth of global oil flow. Enforcing a blockade inside it turns a bombing campaign into a shipping war.

Two things changed the war's character. A single naval interdiction can idle more oil than a night of air strikes. Saudi Arabia's entry converts a US-Iran fight into a wider regional one.

For the global economy, the two are not equal. Air strikes raise risk premiums. A contested chokepoint raises the physical cost of moving crude and can strand cargoes.

Established so far: a US interdiction inside Hormuz, Saudi strikes on Yemen, and a Houthi retaliation claim. Not established: the blockade's reach, or how Iran itself will answer.

What is new

Our earlier coverage tracked US strikes on Iran into a 13th night, with Brent crude breaking $100. The fight has now widened to Saudi Arabia, Yemen and the Strait of Hormuz.

The US military said the tanker was disabled while running the blockade, the BBC reported. Its name, flag and any casualties were not immediately available.

The war widens

The conflict had centred on the US strike campaign against Iran. Saudi Arabia's direct strikes on Yemen mark a widening of the war, The Guardian reported.

The Houthis claimed a strike on Saudi Arabia as the conflict deepened, according to Dawn. They vowed further retaliation, per The Guardian.

The Houthis have already claimed a strike on Saudi soil. Whether they extend that to shipping, rather than land targets, is the pivotal unknown.

The pattern is escalation by widening, not only by frequency. Each step adds an actor or a front rather than more strikes alone. The blockade's logic is economic: choke Iran's oil exports at their exit. The counter-logic is symmetric. If Tehran or its allies threaten all traffic, the strait itself becomes the battlefield.

Hypothesis: Saudi entry and Hormuz interdiction risk drawing Gulf exporters and global shippers into the war. Supporting this: Saudi strikes on Yemen, US enforcement inside the strait, and Houthi retaliation threats. Against this: only one vessel has been reported stopped, and there is no confirmation the strait is closed to traffic.

Unconfirmed: the tanker's identity, the scale of the Saudi strikes and Houthi claims, and whether Hormuz traffic has been curtailed. These rest on initial reports.

What to watch

  • Whether Iran or the Houthis try to close or mine the Strait of Hormuz.
  • Insurance costs and re-routing decisions by tanker operators.
  • Whether other Gulf states join Saudi Arabia's strikes on Yemen.
  • The oil-price reaction to a shift from bombing to blockade.
  • Any US move to escort or convoy shipping through the strait.
  • Statements from Iran on whether it treats the blockade as an act of war.