A group of respected American scholars has been denied visas to China. Their offense? The 13 academics contributed to a book about a province in China where the government has suppressed dissident stirrings. Rather than protest, the universities they work for have been largely silent. The Xinjiang 13, as the academics have dubbed themselves, say that's because U.S. have institutions have an economic incentive to stay mum--attracting Chinese students who pay dollar to attend American colleges. Daniel Golden has been following the story for Bloomberg and joins us with more.