At the US-Mexico border, it's not just law enforcement on patrol. Colorado militias are there, too. Mother Jones writer Shane Bauer went undercover to see these paramilitary groups up close. Then, one Denver teenager gives her thoughts on this election season, while another builds an SUV-sized walking robot. Also, people who manage to disagree politically and still love each other. And roller derby teams -- including in Denver -- are moving away from the kitschy names and dolled-up reputation in an effort to take the sport mainstream.