Ask Americans what they think about Nigeria, and most will have no idea that Nigeria is wracked by an internal genocide that has killed hundreds of thousands of Christian villagers. Even fewer will know the root cause of the murders. Which is why Lara Logan, a host of the Fox Nation program “Lara Logan Has No Agenda,” has produced a 38-minute documentary on the Nigerian catastrophe called “21st Century Terrorism Revealed.” Though working from a distance of 5,000 miles, Logan deployed the voices of Nigerian citizen-journalists who risked their lives to obtain video and testimonies from villagers escaping the genocide. Lawrence Zongo, a high-school history teacher, teamed up with Masara Kim, a respected conflict reporter in Jos, Luka Binniyat in Kaduna, and Tom Garba in Adamawa, as well as many others, to work in a group that Zongo created called “Rural Watch.” In the film, Logan asks Lawrence Zongo: “Are you …