Facebook is rolling out its fact checker to protect its members from fake news. Among the first debunkings is a false story of Irish being brought to America as slaves. What Facebook is doing is essential PR. It is deepening its relationship with its members through watching out for them. It is not acting like a scolding nanny but simply informing its members that independent third-party fact checkers have reason to believe that a story is false. It then leaves it up to the member to accept the story or not. Some might wish Facebook would go a step farther and remove the story from its site. That might come some day, but for now a warning should be enough for most readers. Conspiracy theorists will accept a story as true and reject warnings, but there is little that can be done about them.