“We have entered an era of intense antipolice activism, led by the federal government in conjunction with agitators like Al Sharpton,” Heather Mac Donald claims in her book ‘The War on Cops.’ Just how many times have we entered this era? Twelve years before Black Lives Matter came on the scene, Mac Donald delivered a lecture at the American Enterprise Institute titled “The War on Police.” Her 2003 book ‘Are Cops Racist?’ was subtitled How the War Against the Police Harms Black Americans. Here we go again.”