New Delhi, Aug. 28 -- The executive order Donald Trump signed Wednesday does not simply prohibit new Chinese hardware from the American power grid. It demands that the utilities running that grid begin identifying what Chinese hardware is already inside it - an admission embedded in the policy itself that Washington does not know the full answer.

hardware that had never been disclosed to buyers.

The Federal Communications Commission banned Chinese-made solar inverters with remote communications capabilities earlier this year, following findings that the embedded components could theoretically allow remote access to grid infrastructure. Trump's executive order extends that finding across the broader bulk-power equipment chain. If communi...