This answer depends on which side you are looking from and what is your definition of success. One of the problems for both the US and the French before them encountered was the lack of a clear military objective. For North Vietnam there objective was simple, to clear the aggressors out of their country. They didn't accept the artificial partitioning of Vietnam into North and South. For both the USA and French they had a rather nebulous criteria of stopping the spread of communism.
This takes nothing away from the bravery of the troops on both sides who fought bravely for their countries. The fact that 57000 Americans lost their lives over the 20 years of the war that was instigated by CIA aggression cannot be overlooked.
So in answering the direct question:
From the American side it was a total disaster. 57, 000 killed many more disabled and the spread of communism not halted.
From the North Vietnamese viewpoint it was a total success because the “invaders” were forced out of Vietnam which was unified.