In reality, Khmer Rogue and Viet Cong would be at each other's throats by now. Pathet Lao would be standing back, "Not my problem".
It's definitely a Second Indochina War image where the three were fighting together, yeah. The Khmer Rouge and PAVN (Viet Cong were only in South Vietnam) actually got along well, then.
Of course, they turned on each other almost immediately for the Third Indochina War (and Laos actually joined with Vietnam against Cambodia instead of sitting out, but was very much a minor partner), but so it goes...
It's definitely a Second Indochina War image where the three were fighting together, yeah. The Khmer Rouge and PAVN (Viet Cong were only in South Vietnam) actually got along well, then.
Of course, they turned on each other almost immediately for the Third Indochina War (and Laos actually joined with Vietnam against Cambodia instead of sitting out, but was very much a minor partner), but so it goes...
Viet Cong were practically a branch of the PAVN, so it's more of a technicality to differentiate them (kind of like trying to say the Condor Legion wasn't under German command because it was operating in Spain for Franco's benefit).
And the histories I've read, the three were not remotely close. At best, they provided assistance among one another in short spurts, but overall, the trusted each other about as much as they trusted France, China, and the US (i.e. not at all). People make the mistake in thinking that because they were all under the Communist banner, they were inseparable. Reality says otherwise
Viet Cong were practically a branch of the PAVN, so it's more of a technicality to differentiate them (kind of like trying to say the Condor Legion wasn't under German command because it was operating in Spain for Franco's benefit).
This isn't true, at least before 1968 when PAVN basically took over the war in its entirety. The NLF started very much as a home-grown insurrection in South Vietnam, while PAVN were the official military of North Vietnam. The NLF became a subsidiary of PAVN over time, particularly after most of the local cadres were practically wiped out in 1968, but they weren't created as an offshoot branch of PAVN in the same way the Condor Legion was of the Wehrmacht.
And the histories I've read, the three were not remotely close. At best, they provided assistance among one another in short spurts, but overall, the trusted each other about as much as they trusted France, China, and the US (i.e. not at all). People make the mistake in thinking that because they were all under the Communist banner, they were inseparable. Reality says otherwise
The enemy of my enemy is my enemy's enemy. Again, while it's certainly true that they ended up not trusting each other, earlier on they did work together (at least begrudgingly) against the Western forces. The Ho Chi Minh Trail, for example, would never have been so successful if it wasn't for the active assistance of both the Panthet Lao and the Khmer Rouge. The real kicker of relations down the hill was when 1) the Western militaries pulled out, taking away their mutual enemy, and 2) when Vietnam sided fully with the Soviet Union after Cambodia sided with China.
As to the last point, sadly it's all too common for people to view international relations solely through their own personal lens for "good guy/bad guy". For another example, see the "Axis of Evil" speeches in the early 2000s claiming that Iran and Iraq were somehow working together, never mind the eight-year-long war between those countries that neither had any desire to forget.
