Thats fantasy as well, The US dropped more bombs on North Vietnam than the whole of WW2; what could 2 super carrier do to the Ho Chi Men trail that the Stratigic bomber command cannot? especially, when the HCM trail is in Burma, - 100 KM inland, staying safe from any silkworms the Vietnamese may have, your combat air support will have to fly 200 km one way, through hostile airspace with a possibility of SAM and MIGs.
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Don't believe in the classical interpretation of the vietnam war by mainstream media and story spinners. If the USA feared Soviet intervention, there would not have been a cuban crisis. If US feared an all out war with the SU, the USA would not have supported China nuclearly during the sino-soviet crisis. The fact is simple that the US was not prepared for the vietnam war and did not have the determination to win it at the price that it was costing.
Right, the lesson of Vietnam was that air interdiction alone couldn't shut down motorized supply routes through the jungle. But had the US opted to invade North Vietnam and Cambodia, then it could have cut the supply lines with ground forces. Also, the most of the air ordnance the US dropped on N Vietnam was wasted. It would have done much better with a systematic firebombing campaign against Hanoi, Haiphong, and every Vietnamese city, in order to deplete the manpower available to the NVA.
EDIT: They also should have followed it up with systematic bombing of food supplies and chemical/biological warfare against the Vietnamese rice crop. Unfortunately, the US was too sensitive to take civilian casualties to adopt such a strategy. Given that the Vietnamese people were engaged in a total war against the United States, they should have been regarded as legitimate military targets, however.