Last week, we talked with a woman named Nacole, whose 15-year-old daughter was coerced into the sex trade and sold to johns through online forums. After her daughter was rescued, Nacole took it upon herself to champion a bill, which is now a law, in Washington state. The law requires sites like Backpage.com to obtain documentation proving that the escorts they advertise are at least 18. But in addition to these laws, what else should be done to protect children from the world of sex trafficking? Nicholas Kristof, columnist for our partner The New York Times, has delved extensively into this question.