Allen Weiner, co-director of the Stanford Center on International Conflict and Negotiation, discusses the attack in Libya that left four U.S. diplomats dead, including Ambassador Christopher Stevens.

U.S. ambassador to Libya Chris Stevens, who was killed along with three embassy members in Libya, had strong Bay Area ties -- from playing tennis at Piedmont High to getting a law degree in San Francisco.

He was described by colleagues and former teachers as unflappable, upbeat, honorable and courageous.