I would add that this didn’t seem to be something Giap would say-—he was more involved in the tactical situation in the South, not the STRATEGIC situation in the North. It is entirely possible the quotation is accurate, but it needs to be attributed to someone else.
One more source. You shold look at a book called “The Transformation of American Air Power,” by Benjamin Lambeth. It sounds like something he would have found.
“I heard recently on the Rush Limbaugh show this quote.”
I listen to Rush everyday. I have never heard him utter something anywhere near what you attribute to him. I have heard him say (something along the line of ) it is now common knowledge to anyone that pays attentiont that we had North Vietnam on the ropes and almost defeated according to their military leaders of the time and that the greatest asset the Communists had during the Vietnam war was Walter Cronkite on the evening news every night.