Paul Diamond wrote:
Something missing from your narrative. Vietnam had rubber plantations, vital during WWII for tires/gaskets/tubes, etc. And Vietnam also had discovered OIL not too long before NVA began activities against the South. There were some 'big money' companies working to influence the USA policy toward South Vietnam. When France was ready to throw in the towel, pressure within the USA saw fit to continue and expand our involvement with this country.
Uh, the Japanese had that rubber all during the war and by the time the war was over artificial rubber for tires etc. was well on the way to suppling the US market - after all, in large part it got us through the war. 1940 a new type of synthetic rubber, much cheaper from Goodrich; 1942 the first four pilot plants made 2241 tons, 1945 production was up to 920,000 tons per year. So the US didn't need SE Asia's rubber any more.
In North Vietnam the Song Hong gas field, relatively small with only 40 wells total by the late 70's was found by Soviet techs in 1969* and newer exploration with modern tech today has found a lot of mostly gas in the area though they still carry on exploration and keep predicting big things-sometime-maybe for petroleum.
The first oil field in what was South Vietnam was discovered in February of 1975 and the US closed its embassy and SVN was over run in April 1975. Then another a second oil field was found in 1988 and the third about 2003 and they are all off shore fields.
So oil wasn't a major factor either.
And as recently as last year the US was independent thanks to shale oil production. But that has since been cut back so we need to import oil again. Yes the last few years we imported some grades of crude petroleum for some uses but we exported more of other grades for a net export balance in our favor. One I know of is high sulfur oil which we exported/traded for low sulfur oil because it is much cheaper to refine for the US market anti-pollution specs.
Nope oil and rubber or other resources were not a big factor in our Vietnam War.
And we never did legally declare war - the US is about the only nation that requires the legislature and president to pass and sign a formal declaration of war to make it a real War.
So oil did not enter into the causes of the US in Vietnam. It came about because we backed France in trying to get back its colonies, then we backed the "democratic" South of the split nation as part of the US's overall containment policy towards communism.
It was politics, not money.
*US advisors in Vietnam 1954, combat troops first arrived in March 1965, I was there Dec 66 to Jan 69, last US combat troops pulled out in 1973.