The militarization of local police was a major reason for massive protests last month after Michael Brown was shot by an officer in Ferguson, Missouri. It’s no accident that the force resembled the SWAT teams begun in Los Angeles in the aftermath of the Watts Riots of 1965. Olivia Katrandjian is a reporter for the series "SWAT: Mission Creep" for Retro Report, a project of the New York Times.