WASHINGTON - A spy-agency analysis released Thursday contends a second attack on U.S. ships in the Gulf of Tonkin never happened, casting further doubt on the leading rationale for escalation of the Vietnam War. Much as faulty U.S. intelligence preceded the invasion of Iraq, the mishandling of intercepted communications 40 years earlier is blamed in the National Security Agency paper for giving President Johnson carte blanche in the conflict. The agency put out more than 140 long-secret documents in response to requests from researchers trying to get to the bottom of an episode that unfolded in the South China Sea...