Twitter co-founder Evan Williams talks with the Atlantic's James Fallows about social media and why optimism is a key ingredient for creating successful technology companies. Peggy Johnson of Qualcomm, Larry Smarr and Susan Shirk of UC San Diego follow with comments on the future of technology in China, the US and around the world. This program is part of The Atlantic Meets The Pacific series hosted by The Atlantic and UC San Diego. (#22774)