Instead of battling over tariffs, Washington and Beijing have turned to a potentially far more harmful strategy: flexing their control over global supply chains.

If international trade is a game of chess, China has the U.S. in check — with few good options for the next move. Why it matters: The trade war has exposed just how deeply the U.S. economy is at the mercy of an accident of geology — China's supply of the rare earth minerals that power our modern high-tech society.