A few weeks ago, my wife and I visited VIetnam for the first time. In planning the trip, I resisted visiting Ho Chi Minh City; we didn't go further south than Hoi An (near Da Nang). At first, I had a hard time articulating this reluctance to visit Saigon. But after several days, it became clear.
The North had won, so they were in a position to move past the US's role. I had opposed the war from beginning to end, so it was a relief to see that the damage -- however extensive -- was temporary.
The "South" had lost the war; the US had abandon "them". (I use parentheses because many in the South made great sacrafices to reunify their country.) This must have been a bitter pill to swallow. The fact that I, and so many of my countrymen, strove to end the war sooner, would be little comfort to the ultimate losers. I can face this abstractly, but I preferred not to confront it face-to-face.
Judging from attitudes in Da Nang, I probably exaggerated this dilemma. Walking along the beach front there, reminded me more of Ipanema than the war in Vietnam.