...What about training troops? What about the CIA engaging in psychological warfare against the North?
Training troops comes under the education part. The CIA trained the South Vietnamese military on torture techniques, but to my knowledge there is no clear evidence that CIA performed the interrogation themselves. I think that is what you mean by pyschological warfare. It is not war until one of our guys kills one their guys. Not to be flippant, but before then, it is just business. Also, if that is the case, then we have been in a permanent state of war since the CIA was founded. That includes every president, including the peace loving Jimmy Carter.