How Cellphone Chips Became a National-Security Concern

The U.S. made clear this week that containing China’s growing clout in wireless technology is now a national-security priority. Telecommunications-industry leaders say such fears are justified—but question whether the government’s extraordinary intervention in a corporate takeover battle that doesn’t even involve a Chinese company will make a difference.

The Committee on Foreign Investment in the U.S., a panel that reviews foreign takeovers on national-security grounds, laid out this week a number of reasons why it was probing...