(Bloomberg) — Former U.S. National Security Advisor Susan Rice sparred with a senior Chinese diplomat on Twitter in an unusual and heated dispute over race in Washington. In a series of Tweets apparently aimed at making a broader point about diplomatic divisions over the mass detention of Muslims in China’s Xinjiang province, Lijian Zhao, a diplomat posted in Islamabad, said on Sunday that if “you’re in Washington, D.C., you know the white never go” to the southeastern part of the U.S.