NEW YORK CITY -- The World Trade Organization’s national security exemption allows the U.S. to ban Chinese information and communication technology exports, a Commerce Department official said on Wednesday. Nazak Nikakhtar, the assistant secretary for industry and analysis at the International Trade Administration, spoke at the Aspen Institute’s fourth annual cybersecurity summit. She cited Article XXI of the General Agreement on Tariffs and Trade and other similar WTO rules as backing for actions the Trump administration is taking to restrict...