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?


China invaded them right after the US did…
And the scale of that was not even 1% of the American invasion and was over in a month.
There’s also historical animosity here, China before the CCP didn’t have great relations with their southern neighbors and one communist revolution doesn’t make those geopolitical grudges go away. China has do a lot recently to try and repair that divide, seemingly with some success (if what I’ve read is true China-Vietnam relations have improved a lot in my lifetime at least).
I don’t see what centuries old animosity should be overcoming the, within living lifespan memory of the imperialists slaughtering a good portion of your countrymen in a decades long campaign of extermination. That’s magnitudes worse than anything “China” before the PRC has done for centuries back. Cozying back up with America after that is shameful and a failure of leadership and education. There’s no other way to put it.
Okay, then why do you think Vietnam warmed to the US and only recently started having better relations than China?
Ideological capture, market penetration, brainwashing, media bias, failure of principled marxist education to be applied in schools. The reasons Vietnamese people like America is the same reason that people in the Philipines and Thailand do. Money and media and intellectual capture of institutions, neocolonization.