It would be more about keeping Vietnam at bay than it is about saving the Khmer Rouge. And OTL Vietnam and Thailand did have skirmishes with each other.
https://en.m.wikipedia.org/wiki/Vietnamese_border_raids_in_Thailand
As to the original question, I can’t imagine what would happen to ASEAN if Thailand intervened militarily. Even without one of its members intervening ASEAN was quite divided.
Other than Thailand, Singapore and Philippines were also wary of Vietnam.
On the other hand, Indonesia and Malaysia were more favorable to Vietnam. Not because they were pro-Hanoi but because they want a strong Vietnam as a buffer state to China.
They shielded them OTL into the 90s. Plus, to stop Vietnamese expansionism and gain territorial concessions in the west.The first question is why would thailand want to save the khmer rouge?
They shielded them OTL into the 90s. Plus, to stop Vietnamese expansionism and gain territorial concessions in the west.
Maintaining it as a buffer state between It and Vietnam.The first question is why would thailand want to save the khmer rouge?
As for the OP, Thailand eventually loses. Vietname is the Finland of the latter 20th century, punching way above their weight. The Vietnamese in their mind were fighting for national existence, Thailand in southeast asia is viewed as a well-to-do country, so they would see the Thai involvement as an encroachment backed by the US and they will fight hard. THe THai will be laid back and wonder why they are doing this and will eventually be outlasted by the Vietnamese.
I think you eviscerated your point in your very post. As you point out, the thai right off the bat supported the khmer rouge. The OP merely asks could the thai get involved. Of course they could. And, being that they had no problem policy wise supporting the khmer rouge OTL, the question simply is what would be necessary to make the Thai support the khmer rouge exclusively. To fulfill that part of this TL, we would need the khmer rouge to be much stronger initially in their fight against vietnam so they look like they are worth supporting and more US pressure to assist thailand in even getting seriously involved. Granted, we would need PODs back into the 1960s to make this happen and perhaps even an early death for pol pot after he takes power (an TL where Hun Sen takes power after Pol Pot's death would be ironic, but not impossible given Hun Sen's instincts and the fact he was already so powerful in the late 70s).They shielded them into the 90s after Vietnam expelled them.
As noted before, we can't use how Thailand acted towards Cambodia and Vietnam after the Vietnamese were already in control of Kampuchea to posit that they would act that way before Vietnam has gained control.
And why not? Well because after Vietnam invaded, Thailand sheltered the Khmer Rouge, but mostly as a part of a coalition of Cambodian parties (including non-communist republicans and royalists) called the Coalition Government of Democratic Kampuchea. This was from 1982. Thailand seemingly had little interest in supporting the Khmer Rouge, except as a part of a broader (and mostly non-communist) element of Kampucheans who would be opposed to the Vietnamese-backed regime.
And when Vietnam invaded Kampuchea in full scale force in 1979, Thailand offered immediate support to Son Sann to form a non-communist resistance force.
What was being posited by the OP is Thailand supporting the Khmer Rouge as an actual government in Cambodia. If they did so, how could they have gotten Son Sann and his Khmer People's National Liberation Front to be included in a coalition government with the Khmer Rouge? They can't force the Khmer Rouge to do so while the KR maintains actual power, unless after resisting the Vietnamese they then turn on the Khmer Rouge and start fighting the actual Kampuchean government and army....which calls into question again, just why they would have saved them in the first place?
The Vietnamese defeated and outlasted the US...if the US had the best military on Earth, even if Thailand had the second best i don't see how that helps them.I wouldn't bet on that neccessarily. They didn't get beat by the PRC due to a combination of the poor quality of the PLA and being on the offensive. They won against the Khmer Rouge because of the terrible state of the Cambodian military. I don't know how well they'd do going toe to toe against the Thais in a conventional fight.
Anybody got any sources on the quality and strength of Thai forces of the time?
The Vietnamese defeated and outlasted the US...if the US had the best military on Earth, even if Thailand had the second best i don't see how that helps them.
Could they at least crave out a buffer state in western Cambodia and any reason why the war would spread to Lao ?Even still, Vietnam just has to outlast Thailand and I doubt Thailand can kick them out of Laos and Cambodia entirely.
I think you eviscerated your point in your very post. As you point out, the thai right off the bat supported the khmer rouge.
The OP merely asks could the thai get involved. Of course they could.
Maintaining it as a buffer state between It and Vietnam.
Could they make an agreement with Vietnam dividing Cambodia into a pro-thai government under Son Sann and pro-Vietnamese one under Pen Sovan?And strategically, it would be pointless for Thailand to get involved in an actual shooting war with Vietnam to maintain Kampuchea as a buffer state
Could they make an agreement with Vietnam dividing Cambodia into a pro-thai government under Son Sann and pro-Vietnamese one under Pen Sovan?