Horton, a university lecturer in English literature, reinvented himself in his forties as a one-man research programme into what the Burmese army, the Tatmadaw as it is known, was doing to the Burmese people.
In 2000 he undertook a four-month journey through the eastern marches of Burma, heartland of the Karen, the Shan and the Karenni ethnic groups. It was hair-raisingly dangerous: the strongholds of the ethnic groups have all been destroyed, their populations forced into the jungle or across the border into Thailand. The soldiers of the Tatmadaw can turn up anywhere at any time and their treatment of those they consider their enemies is brutal. One village survivor recounts how four villagers blamed by the army for aiding insurgents were buried in the earth up to their necks, then soldiers smashed their heads with shovels until they died.
On his first day in the Karen region, Horton himself managed to scramble into a hut just as a party of soldiers approached. He heard them fixing their bayonets outside – "a terrible noise". Somehow they passed his hut by.
What Horton was filming and documenting was the bitter outcome of the 50-year war being waged between the modern forces of the Tatmadaw and the rag-tag insurgent armies grouped around the border – an unequal war of attrition which year by year the army of the lowland Burmans, who rule the country through the military junta and who constitute about 60 per cent of the population, was slowly winning.
But that cooking pot made him stop and think. Why destroy a cooking pot, so thoroughly and methodically that it could not be used again? "Why do something so arbitrary and ludicrous?" he said. He looked around the village of bamboo huts that the army had razed. He saw other mundane implements given the same treatment as the pot: looms and rice pounders smashed, for example. The domestic animals, all slaughtered. On all sides, the things that make village life possible had been rendered useless.
"I thought, these people are not intended to live," he said. Once the army had departed, the villagers who had fled from them into the jungle might creep back and rebuild their flimsy huts. But what would they eat? If they found something to eat, how would they cook it, lacking pots?
Taking in the scene, the word "genocide" came to his mind.
As defined in the 1948 Convention on the Prevention and Punishment of the Crime of Genocide by the United Nations, genocide is any attempt, whether successful or not, "to destroy, in whole or in part, a national, ethnic, racial or religious group".
Horton looked around and asked himself, is this what is happening here? Is the Burmese junta seeking a final solution to the problem of its troublesome minorities?
A rumpled, shambling man of 53, Guy Horton's obsession with Burma came about by accident. He was born in India, in Nainital in the foothills of the Himalayas where his parents were working, and lived there until he was seven. In England, like many born and partly raised in the subcontinent, he always felt something of an outsider. Burma is not India, but there is a lot in common. "When I first got to Burma," he said, "I felt as if I had come home."
In Oxford in the mid-1990s, where he was lecturing, Burma and its unending tragedy hit him with a special force, for reasons he finds hard to articulate. He proposed to the city that they make Aung San Suu Kyi, leader of Burma's opposition, who has been under house arrest for years, an honorary citizen. Suu Kyi's husband, Michael Aris, an expert in Tibet at Oxford, got in touch to thank him. They found that they had been at school together. "Michael asked me to become a friend of the family, and I became very close to them," he said. "It was Michael who urged me to go to Burma in 1998."
That was his first trip to the country, and he went in the front door like a tourist. Like many first-time visitors, he was unprepared for the viciousness of the regime. In Mandalay, Burma's second city, he got into conversation with local people and diffidently raised the name of Aung San Suu Kyi. "Two ferocious undercover policemen immediately came up to me, both over six foot and disguised as monks, and started pushing me around. I managed to run back to the hotel, where the management said my life was in danger and made me sleep on the roof of the hotel for my own safety. It was a turning point in my understanding of the place," he said.
Two years later he returned to Burma, but this time to the eastern border with Thailand, the region which is home to three of the largest Burmese minorities, the Karen, the Shan, and the Karenni. He was going to travel incognito through the heartland of these three groups and document what he found.
The Burmese regime defines the status of the villages in this region by colour coding. Black zones are areas in which the insurgents remain notionally in control and have villages that support them. Brown zones are the areas in dispute between the two sides; white zones are where the Tatamdaw exercise total control. Black zones constitute about 10 per cent of the region inhabited by these three groups, and the area is rapidly shrinking. "The image the regime uses is of a lake that is drying out," Horton explained. "When it is dry – when all the black zones have turned white – you catch all the fish."
Thirteen years ago, with the Canadian photographer Greg Girard, I entered the Karen region from Thailand, when it was still firmly under the control of the insurgents. It was a nerve-wrecking passage, first in the back of a pick-up truck driven by Karen activists down remote logging roads, then across the river that demarcates the Thai-Burma border in a boat powered by a car engine; nerve-racking and extremely hot and humid, but with hindsight we were relatively safe, because the Karen were still calling the shots. Disembarking from the boat, it was a short scramble up the muddy bank into Manerplaw, the military HQ of the Karen and an asylum for hundreds of opposition supporters who had fled from the lowlands.
Manerplaw, however, was destroyed by the Tatmadaw in bombing raids in 1995, and survivors fled across to Thailand or into the bush. When Horton made the same crossing five years ago, he was extremely lucky to survive the first night.
"I was only 15 yards inside Burma," he said, "when I learnt that the Karen guide I had arranged to meet had been shot dead. The hut was filled with bullet holes, the thin rattan and bamboo walls ragged and transparent. Just after nightfall we were approached, shouted at, and a powerful torch was shone through the frayed walls. I lay face down on the earth and prayed. I could hear the metallic sound of safety catches being released, then the metallic sound of bayonets being fixed. God knows how they didn't find me."
He pressed on with his trip through the jungle. Walking along the established footpaths was out of the question: everywhere the Tatmadaw had visited they had left land-mines along the paths. Horton's local helpers put him on the back of a 75-year-old elephant. Elephants never forget, as he knew, and this one remembered long-vanished footpaths from village to village which had reverted to bush years before, and which therefore had not been mined. The elephant, and Horton, blundered through unscathed.
What he found everywhere was spectacular devastation. "Typically," he said, "the army will move into a village, confiscate anything of value, slaughter the animals and destroy the cooking pots and looms. The village is burnt and usually mined. The inhabitants are relocated to a new site, usually with inadequate food and water, where they are forced into labour schemes such as road-building. In the long run, many just can't survive."
Indeed Horton now believes – it is the thrust of the case he makes in his 600-page report, Dying Alive, which he intends to present to the United Nations – that it is the intention of the regime that they should not survive.
It is a rare totalitarian regime which commits its murderous schemes to paper. Burma's is no exception. There have been the occasional loose remarks that have caught the attention of observers. In 1989, one year before the election won by Aung San Suu Kyi (but which the regime then ignored), the chairman of the junta acknowledged that the death toll in Burma's ethnic wars "would reach as high as millions". Three years later, in 1992, the Health Minister, Ket Sein, reportedly boasted to a large meeting in Rangoon: "In 10 years, all Karen will be dead. If you want to see a Karen, you will have to go to a museum in Rangoon."
But proof of genocide is not to be found in official documents, Horton believes, but in the evidence of his eyes and his video camera and tape recorder; assembled during the long trip of 2000, and several shorter ones during the following four years.
Taking statements from victims in Thailand, using photographs, maps and films, the atrocities he has documented include slave labour, systematic rape, the conscription of child soldiers, massacres, and the deliberate destruction of food sources and medical supplies. The people of the Karen, the Shan and the Karenni were being killed, and when they weren't killed outright they were killed by inches: by being forced to labour so hard that they would drop dead from exhaustion, or contract small injuries from which, there being no medical supplies, they would die as a result of infection.
Women were systematically raped by soldiers. "Burma defines ethnicity through the father," writes Nicholas Thompson in an article on Horton in the American magazine Legal Affairs, "so a child born as a result of rape means one less minority and one more Burman."
Horton, who admits that his trips into Burma "were incredibly arduous – it nearly destroyed me physically," is now in a unique position to argue that the ethnic wars in Burma now be viewed in a much different and far sterner light. "What I could bring," he said, "was a contribution of systematic thought."
He now plans to persuade the United Nations that the violence committed by Burma, which ratified the Geneva convention on genocide in 1956, amounts to genocide.
"I would go through the jungle," Horton said, "and I would come across traumatised groups of extremely weak people, huddled together under makeshift shelters. They gave off a strange sense of numbness and weakness. They had very little food: they foraged what they could in the jungle, but it was not enough. As they told me, they were 'dying alive.' "
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