The remote, mist-wreathed Hindu temple of Preah Vihear is not an obvious place to start a war. Lost in the jungly Dangrek highlands of the Thai-Cambodian frontier, it hasn't seen much activity since its heyday in the 11^th century. Until recently the only visitors were intrepid, saffron-robed monks, or the occasional smuggler or refugee.

But now it is the epicentre of a military conflict which has seen a series of bloody skirmishes, and the killing of two Cambodian soldiers. The international fracas could, very easily, flare up until full-scale war between the two South-East Asian countries.

Why?

The proximate cause of the scuffle is a land dispute. In 1962, after a decades-long argument about ownership, the International Court of Justice in The Hague awarded the temple to Cambodia. Crucially, the land surrounding the temple was left in Thai possession: this became a factor in 2008, when the wistful grey ruins were named by UNESCO as a World Heritage Site.

The Cambodians were delighted with the UNESCO designation, until they realised that they would not entirely benefit from the anticipated tourism: the Thais would also gain, by ferrying visitors to Preah Vihear across Thai territory. The Cambodians have therefore laid a second claim to the surrounding lands; the Thais have stoutly objected, with some Bangkok politicians urging annexation of the temple itself.

In other words, it's all very complex. But also, on the face of it, quite trivial: certainly not a cause for shooting people.

So what is the ultimate rationale behind the face-off? To find the answer, you have to travel across the border, and ask people what they think of their neighbours, and thereby uncover the envenomed psychology.

In Bangkok the common attitude to Cambodians is mild contempt, tinged with anxiety. Many Thais dismiss their darker-skinned neighbours as hopelessly backward. Yet Thais also worry about the unpredictably pugnacious Khmer temperament, and therefore exercise a certain wariness: the same way a husband might tread carefully with a pre-menstrual wife.

Visit the dusty boulevards of Phnom Penh and you find fiercer and stronger emotions towards the kingdom of Siam. "They look down on us" say Cambodians, "The Thais think they can walk all over us, just because they are bigger."

Unkind shrinks might call this the "runt complex". Relatively small and impoverished, Cambodia suffers a profound insecurity about its status, and takes any slight from its mightier neighbours - Thailand and Vietnam - very badly. And Khmers have historical reasons for feeling insecure. Over the centuries Cambodia has been invaded and conquered from both sides: the last Vietnamese incursion came in the late 1970s, when the Vietnamese overthrew the apocalyptically communist Khmer Rouge regime.

Finally, there is a deep Cambodian nostalgia: for a time when they were supreme. During the Angkor period, of the 12^th and 13th centuries, the Khmers ruled an empire which encompassed much of Indochina, including Siam and Vietnam.

The Cambodians have never forgotten this ancient era of glory. The name of the Khmer Rouge government, Angkar, "the organisation", was a deliberate echo of this long-lost grandeur. The name of the town nearest the great temple complex of Angkor Wat: Siem Reap, actually means "Thailand defeated".

For all these reasons the dispute of Preah Vihear drills deep into the root-canal of Cambodian anxiety. That means it is very possible that the temple skirmishes will escalate into something quite nasty - unless wiser counsel prevails.

Meanwhile, the temple itself slumbers away on its hilltop, and the jungle rain patters down upon the ancient carvings of Shiva as he dances in endless triumph over the evil Demon of Ignorance.