Book excerpt: Cyber influence is an ongoing source of power in the international security arena. Although the U.S. has an enormous cyber information capacity, its cyber influence is not proportional to that capacity. This pub. by the Nat. Defense University Center for Technology and National Security Policy discusses impediments to American cyber influence. It also offers a multifaceted strategy to enhance the influence of the U.S in cyberspace that differentiates the circumstances of the messages, key places of delivery, and sophistication with which message are created and delivered, with particular focus on channels and messengers.