tour staffour city's recently visited tacoma. learn more about tacoma and other stops on our tour on c-span.org. you are watching american history tv all weekend, every weekend on c-span3. >> monday night on the communicators. >> hackers hack humans. >> we are at the black hat conference in las vegas talking about cyber security and cyber threats with the ceo of net squared. >> it's not easy to patch a very large organization and keep on patching it months after months. think ofhave to really the defense. to itnot keep reacting anymore. we have to look for threats. we to set booby-traps. we have to create customized environments. we have to engage in threat hunting. >> watch the communicators monday night at 8:00 eastern on c-span2. this week on real america, give yourself the green light. the 1954 general motors film encouraging citizens to support programs to improve roads and highways. here is a preview. [whistling] >> hey pal, what is the do? >> load and unload buddy. with 54 million vehicles on our streets and roads today, 5