Cambodia?
In 1965-66 LBJ arranged a game or make-believe with Prince Sihanouk of Cambodia. They would both pretend that the US military was not in Cambodia.
The anti-LBJ pro-McCarthy demonstrators well documented that LBJ did have troops in Laos and Cambodia exposing the pretend game. (My artillery unit was in Laos shooting up the HoChiMinh trail in 66-67.)
So when Nixon became president, the left accused him of expanding the war to Laos and Cambodia. The Left knew full well that there was no expansion. It was a continuation of LBJ policies by Nixon.
Thus we had the Kent State riots for nothing. And protests at Yale and many college campuses for a bogus reason.
What artillery unit were you with and where were you stationed in Lao? Did you operate out of Tchepone?
I seriously doubt that we had any regular troops in Cambodia in 1966. Sihanouk declared war on the Khmer Rouge in 1968 and Gen. Lon Nol wiped out most of them in the western Cambodia campaigns. The survivors fled to N. Vietnam and Red China for further training and refitting before they began to reinfiltrate in the early 1970’s.
I just missed seeing the body of a KIA Red Chinese soldier in Cambodia in November 1970. I did see his Mao button and diary (in Chinese). He appeared to be an advisor. Not sure if he was a local Cambodian Chinese recruited by the reds to go to Red China, or was a Red Chinese officer to start.
I know about the SOG ops but they are not regular Army units.
First No. Vietnamese regular units in SVN are now being dated at least as early as 1963, if not earlier. One NVA high ranking officer/defector I interviewed in 1970 had been stationed in Laos in 1959 as part of the PAVN secret army.