evidence: President Donald Trump’s first secretary of defense, retired Marine Gen. James Mattis, said in a remarkable 650-word statement to The Atlantic on Wednesday that the President is actively trying to divide the country and urged Americans to unite without him. Mattis has avoided directly criticizing Trump since his ouster in December 2018, but that changed after the administration used strong-arm tactics and dispatched authorities in riot gear to clear peaceful protesters in front of the White House this week so Trump could hold a photo op. Mattis, once the loyal general, unloaded on Trump and his threat to use the military to patrol US streets, which Mattis said would create a dangerous tension between the nation’s citizens and the troops who are meant to protect them. [...] - The military has only been used in US streets very rarely, most recently in Los Angeles in 1992. Trump can deploy the military to Washington, because it is a federal city and not party of a state. During the Civil Rights era, presidents used the Insurrection Act, an 1807 law, and deployed the military over the objections of governors. But Mattis argues here that the divide between civilian law enforcement and the military is part of the bedrock of US society.