Based on this chart of Chinese oil reserves and the estimated price they will need to pay (no discounted Iranian oil) China is going to be in a world of hurt. It's hard to overestimate the impact to China if the Strait of Hormuz remains closed. This makes it hard to understand why China would supply weapons to Iran. I think Trump is pursuing a great strategy by letting the Strait remain closed. It will devastate Iran economically and China will face economic collapse if they don't get involved in opening the Strait themselves. All while the US oil companies rake in massive revenues. Trump can also invoke the War Powers Act to ensure domestic needs are prioritized over exports.