Yes but until the later stages of the war, NVA units were essentially still guerilla orientated units, heaviliy reliant as well on the communist infrastructure in S. Vietnam and local support. At the early stages the NVA were not 'conventional' in the same sense of the word as say the some western armies were at that period. Army policy as whole remain deep-rooted in conventional warfare doctrine, based on a strategy of attrition and maneuver, which is natural as this was and is an area the U.S. excels in. The fixation with body counts is a prime example, and was also used in Afghanistan and Iraq. American search and destroy missions in the South, with their heavy reliance on firepower, whilst often failing to create any decisive results, had the effect of alienating a portion of the population.
Bear in mind that though the U.S. was worried that a victorious North Vietnam would export the 'revolution' to other parts of SEA and that a unified Vietnam, under communist rule, would be a stooge of Moscow or Peking, the U.S. was not prepared to risk Soviet or Chinese intervention. American units on the N.Vietnam Chinese border would most certainly have resulted in a Chinese military reaction and instead of eradicating the communist presence in South Vietnam might have had the opposite effect of creating a bigger and more widespread insurgency problem.
In hindsight we know that the N.Vietnamse leadership had no interest in exporting their 'revolution' anywhere but at the height iof the ColdWar, this was a great concern to the U.S. and it's allies. Robert McNamara's book - 'In Restropect' explains how both sides misunderstood and misjudged each other's intentions. At the end of the day, the North Vietnamese were prepared to fight for decades and at a huge cost in human lives to achieve their goals, the U.S. wasn't. The key question that intersts me for purposes of debate, is whether the U.S. would have eventually achieved it's political goals in South vietnam if at the onset the insurgency campaign was conducted in a more effective manner, involving more coordination with the military and civil authorities to deal with the historical, political and social problems unique to Vietnam and had the neccessary doctrinal and mindset changes had been done.
If you haven't, I'd really recommend you get hold of Bernard Fall's books on the French involvement in Vietnam and his thoughts on early American involvement there.