It goes all the way back to Truman:
Letter to President Harry Truman, February 16, 1945. The letter was never answered and was not declassified until 1972
DEAR MR. PRESIDENT:
Our VIETNAM people, as early as 1941, stood by the Allies' side and fought against the Japanese and their associates, the French colonialists.
From 1941 to 1945 we fought bitterly, sustained by the patriotism, of our fellow-countrymen and by the promises made by the Allies at YALTA, SAN FRANCISCO and POTSDAM.
When the Japanese were defeated in August 1945, the whole Vietnam territory was united under a Provisional Republican Government, which immediately set out to work. In five months, peace and order were restored, a democratic republic was established on legal bases, and adequate help was given to the Allies in the carrying out of their disarmament mission.
But the French Colonialists, who betrayed in wartime both the Allies and the Vietnamese, have come back, and are waging on us a murderous and pitiless war in order reestablish their domination. Their invasion has extended to South Vietnam and is menacing us in North Vietnam. It would take volumes to give even an abbreviated report of the crisis and assassinations they are committing everyday in this fighting area.
This aggression is contrary to all principles of international law and the pledge made by the Allies during World War II. It is a challenge to the noble attitude shown before, during, and after the war by the United States Government and People. It violently contrasts with the firm stand you have taken in your twelve point declaration, and with the idealistic loftiness and generosity expressed by your delegates to the United Nations Assembly, MM. BYRNES, STETTINIUS, AND J.F. DULLES.
The French aggression on a peace-loving people is a direct menace to world security. It implies the complicity, or at least the connivance of the Great Democracies. The United Nations ought to keep their words. They ought to interfere to stop this unjust war, and to show that they mean to carry out in peacetime the principles for which they fought in wartime.
Our Vietnamese people, after so many years of spoliation and devastation, is just beginning its building-up work. It needs security and freedom, first to achieve internal prosperity and welfare, and later to bring its small contribution to world-reconstruction.
These security and freedom can only be guaranteed by our independence from any colonial power, and our free cooperation with all other powers. It is with this firm conviction that we request of the United Sates as guardians and champions of World Justice to take a decisive step in support of our independence.
What we ask has been graciously granted to the Philippines. Like the Philippines our goal is full independence and full cooperation with the UNITED STATES. We will do our best to make this independence and cooperation profitable to the whole world.
I am Dear Mr. PRESIDENT,
Respectfully Yours,
(Signed) Ho Chi Minh
One last item:
"Truman never replied to at least eight appeals by Ho Chi Minh for American support of independence and cooperation on the Philippine model. Ho was then compelled to turn to Beijing and Moscow for material aid against returning French troops."
http://hnn.us/roundup/comments/11737.html