The Iran blockade is turning into a shipping and air-travel shutdown across the Gulf, bad news for global trade, Saudi Arabia's economy, and anyone hoping for calm oil markets.

• US jets have disabled commercial ships trying to break the naval blockade on Iran, with four vessels hit and dozens of tankers turned around.
• Houthi forces killed 12 and injured hundreds in an attack on a Riyadh airport, then warned they will target airports across Saudi Arabia.
• The timing hits Saudi plans to build up tourism, crypto, and AI business — hard to sell a country people cannot safely fly into.
• Trump called the attack terrible but stopped short of promising US help, saying he is talking to both the Saudi crown prince and the Houthis.
• Pipelines have been left alone so far; if that changes, oil prices go from a worry to a crisis.

Outlook: More airport strikes look likely, and the pressure on Trump to either join the Saudi defense or cut a deal with Iran will build fast.