Vietnam never had a legitimate government in Saigon that the people believed in and trusted. There was superpower engagement in a huge way. [In Iraq] we [have] a problem with the Syrians -- but nothing like what the Chinese and Russians were doing for the North Vietnamese. You had basic sanctuary in North Vietnam. The whole situation, I think, was very, very different.
Funny thing about comparisons: they never work if they aren't honest. "Saigon" never had a legitimate government because "South Vietnam" was a creation of the United States, and its government existed only because we prevented national elections in 1956 under the Geneva Accords because our side was going to lose. The US recognized the government of Bao Dai in 1950, then the overthrow by rigged referendum installing Ngô Dình Diem in 1955, and after that the various corrupt military strongmen we played footsie with for our own political ends. Sorta like Saddam whatsisname.
So the suggestion that this time we have a real, honest-to-goodness democratically backed government in Iraq which is free to write its own constitution so long as it meets our approval should be taken under advisement. It's what we said the last time, Senator.
And for the record, since this is still not very well understood, before 1965 or so the Viet Minh were supplied from three sources: leftover weapons from the French colonialists, homemade weapons, and what they captured from us (or what we supplied to our friends in Saigon that they turned around and sold). The Russians didn't really begin supplying the Vietnamese until after they'd given us a couple of black eyes, and the Chinese, no real friends of the Vietnamese, basically just permitted Soviet supplies to move through their territory unimpeded. But thanks for the opportunity to dispel some cherished Vietnam War myths; it's always good to keep in practice.