I think your case is rare and such person would hold an extreme political view which exists in any culture. I live in Anaheim, Orange County, the biggest Vietnamese community here in the US for 15+ years, and I haven't experienced that. I've been through other Vietnamese communities also and I haven't seen such attitude either.
Vietnam War has been a wound to the Vietnamese that would never heal. The new Vietnamese generation after the war rarely think about it except the Vietnamese outside of Vietnam including myself.
