The motivations at work in the Cambodian leadership are much harder to divine.
Former Prime Minister Hun Sen is still the puppet-master pulling the strings of his son, current PM Hun Manet. Publicly he has appealed for restraint by his troops, portraying Cambodia as being bullied by a more powerful neighbour and in need of international support.
Yet his interventions in this simmering border dispute have been decisive this year, in particular his decision to leak a confidential phone conversation with the then-Thai PM Paetongtarn Shinawatra, whose father Thaksin was a long-standing friend and business partner of Hun Sen’s.
Her leaked comments, praising him and condemning her own army commanders for being too gung-ho, were catastrophic for her and her father. Her government collapsed, he has gone to jail, and many Thais, even those bitterly opposed to the Shinawatra family, have been angered by the perception that Cambodia has been meddling in Thai politics.
Thai public opinion is now much more in favour of their army’s hard-line approach to Cambodia.
Can President Trump bang heads together again as he did in July? Perhaps.
But if all he achieves is another ceasefire it will only be a matter of time before fighting breaks out again. And Thailand has said repeatedly that it is not yet ready for diplomacy. Cambodia, it says, must show sincerity before it is ready to try for a ceasefire again.
What that means exactly is not clear, but at the very least it would require a decisive and verified end to the use of land-mines on the border.