https://www.nytimes.com/2017/09/25/us/politics/trump-nascar-nfl-protests.html
But his most conspicuous targets were the highly paid athletes, most of them black, who during the playing of the national anthem at football games have protested police brutality and what they say is the systematic racism behind it. The vehemence was tactical, but also visceral. Mr. Trump has often taken a dim view of race-based protest and, as the onetime owner of a football franchise in a failed start-up league, he believes owners of sports teams should control their employees.
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In private, the president and his top aides freely admit that he is engaged in a culture war on behalf of his white, working-class base, a New York billionaire waging war against “politically correct” coastal elites on behalf of his supporters in the South and in the Midwest.