Neighborhood watches, Guardian Angels, Dads Against Drug Dealers—these are all groups that are founded and manned by citizens stepping up to protect other citizens against the dark side of society. The members are almost always volunteers, family men and women who just want to protect their children, families, and neighborhoods from social elements that prey on the weak and vulnerable. They watch and report things out of the ordinary in their local areas, their vigilance often stops or discourages crime simply by being visible and vocal. But this same innocuous organization of local citizens has been hijacked by governments and...