They both have a bit in common. They’re both communist Asian states that the US went to war with during the Cold War and did not win. But the messaging regarding the two states is a lot different. DPRK is treated like the worst dictatorship ever, that kills you and your family for even thinking that the Kims are less than gods, whilst also starving. But Vietnam, they say… nothing.
Why isn’t Vietnam demonized like DPRK?
Vietnam outright won, so there’s no vassal state to be concerned with, and Vietnam is pretty US friendly now, and not thaaaat communist. Ho Chieh Minh wasn’t a hardcore communist to begin with, he was a cabbie in Boston for a while and was quite open to cooperation. The whole Vietnam war happened because the French raised up a tiny set of Catholic Vietnamese (like 3%) as a master race above the rest of the population. Eventually the Catholic minority tried to ban prayer flags on temples, which if you know Buddhism in that region was not going to fly (pun intended). The French turned over control to the Americans who put in a stooge who played us like Netanyahu and made the whole thing a domino theory thing, basically forcing the Buddhist majority over to the Chinese for support. Vietnam isn’t actually particularly dedicated to communist revolution, they just didn’t want French people taking away their religious rights and it was a convenient bogeyman for the cold war narratives of the time, so nowadays they’re probably more US-aligned than Chinese.