There's just no question that the United States was trying desperately to prevent the independence of South Vietnam and to prevent a political settlement inside South Vietnam. And in fact it went to war precisely to prevent that. It finally bombed the North in 1965 with the purpose of trying to get the North to use its influence to call off the insurgency in the South.
Language and Politics (ed. AK Press, 2004) - ISBN: 9781902593821