The Vietnam War wasn't with the U.S.; it was a
Civil War that America interfered with. The lowland
people were the Viet, who wanted to develop the
country & saw the mountain people as
hillbillies who don't understand the modern world.
The mountain people were the Mon-Khmer
or Hmong, who didn't trust changes being made
to the country, such as embracing communism. The Hmong accepted help from a foreign government, so when the war ended they were considered traitors. As a result, there was much immigration & today most southeast Asians living in the United States are Hmong.