Photo taken on May 19, 2020 shows a U.S. national flag and traffic lights in Washington D.C., the United States. (Xinhua/Liu Jie) White supremacy, the U.S. historian said, is the common thread between the recent mass shootings, everyday police lethality and the overturning of Roe v Wade. CAIRO, June 29 (Xinhua) -- White supremacists are trying to turn the United States into their ideal "nation-state" that fully represents their worldview while fully denying the rights and humanity of everyone else, a U.S. historian has said. "White males who are die-hard white supremacists and their fellow travelers have and will continue...