It showed how easily a change of personalities and a paranoia about communism took the US relationship with Vietnam (and Ho Chi Minh in particular) from friend (and supplier of arms) to foe. What an almighty foreign policy f*ckup.
I'm sorry, did you miss the Cold War, Harry Truman's Containment Policy, and much else in the 1950's? Viet Nam was
a lesser included case of a policy that was very much NOT a f*ckup. As my dad spent some time in Berlin during the airlift, the communists had already shown their true colors, likewise in Korea. (Could Viet Nam have gone differently? Yeah. But it didn't).