"Later investigation revealed that the 4 August attack did not happen; no Vietnamese vessels had been present. Shortly after the events, the National Security Agency, an agency of the US Defense Department, deliberately skewed intelligence to create the impression that an attack had been carried out. "
"Later investigation revealed that the 4 August attack did not happen; no Vietnamese vessels had been present. Shortly after the events, the National Security Agency, an agency of the US Defense Department, deliberately skewed intelligence to create the impression that an attack had been carried out. "
https://en.wikipedia.org/wiki/Gulf_of_Tonkin_incident