SARAH FERGUSON, PRESENTER: It sounds like fiction: an Australian professor in the jungles of Asia advising ethnic insurgents in their fight against the Burmese military.

Security expert Des Ball has a huge international reputation. He's worked with the CIA, the Pentagon and the White House. Former US President Jimmy Carter credits him with advice that contained the threat of nuclear war between the US and Russia.

But there's another incredible chapter to Des Ball's life story, untold till now. For more than 10 years, he's been teaching rebel fighters in Burma the techniques of jungle warfare. During that time, Des Ball was also diagnosed with terminal cancer. Today, he was awarded the Order of Australia.

Matt Peacock tells the story.

MATT PEACOCK, REPORTER: In the jungles of Eastern Burma near the Thai border, rebel soldiers from the ethnic Karen National Liberation Army, or KNLA, are on patrol. They've been fighting for decades against the Burmese Army. Even though they're outnumbered 100 to one, they're a force to be reckoned with.

DES BALL, STRATEGIC & DEFENCE STUDIES CENTRE, ANU: They now for several years have been getting kill ratios of about 100 to one.

MATT PEACOCK: In the bloody 60-year conflict, the rebels have perfected the art of guerrilla warfare, thanks in part to some first-rate outside advice.

DES BALL: The principal technique is to avoid large confrontations. Don't get involved in battles. Use very small numbers of Special Forces guys.

MATT PEACOCK: For the past decade, Australia's most famous military intelligence expert, Professor Des Ball, has been actively supporting the Burmese rebels. His help was acknowledged in this special ceremony inside the jungles of Burma two years ago.

DES BALL: I am very humbled to be here with you, because I admire you all greatly. The fact that you have maintained resistance for more than 60 years now. You have faced overwhelming odds, but you have never surrendered.

ISAAC PO, MAJOR GENERAL, KAREN NATIONAL LIBERATION ARMY: Des Ball has been a good friend to the Karen for many years. Des share his knowledge and skills with us and we appreciate what he did for us.

MATT PEACOCK: Even as the Australian Government's been warming its relationship with the Burmese generals, Professor Ball, one of the world's leading military strategists, has been advising the Karen rebels on how to target the Burmese Army.

DES BALL: A typical strategy, yeah, is to use the snipers to take out the officers. ... How you set up ambushes, which particular battalions, Burmese Army battalions, which officers - some of them are pretty useless, so you don't worry too much about them. Some of them are just gross beyond human imagination. And so planning the intelligence structures that you need to distinguish between which ones you really want to go after.

PHIL THORNTON, JOURNALIST: They called him "The Big Brain". Yeah? "Big Brain". So - and he is. Des Ball is a big brain. He comes across as an ordinary sort of fellow. You know, he's an Aussie bloke, grew up on the farm, supports Collingwood, but underneath that he's got a forensic brain.

MATT PEACOCK: Des Ball is better known to most Australians as the ANU academic who back in the 1980s first exposed the role of America's secret spy stations at places like Pine Gap and Nurrungar.

DES BALL (7.30 Report, 20th August, 1987): Nurrungar is the first point of American knowledge about a Soviet missile launch, a Soviet satellite launch, or in war, a Soviet first strike. And that's a very important function.

MATT PEACOCK: Less well known was the work he did on US nuclear strategies at the height of the Cold War.

Ball worked inside America's top secret nuclear and command centres, advising the CIA, the White House and the Pentagon, where he persuaded them that a limited nuclear war was impossible.

DES BALL: By the time you started using even small numbers of devices, your command and control system starts crumbling. And inevitably, you lose your eyes and your ears and you start moving into very large-scale, all-out strategic nuclear exchanges very, very quickly.

MATT PEACOCK: So a limited strike was a myth?

DES BALL: Yes. Yes.

MATT PEACOCK: He was hailed as the man who saved the world. Former US President Jimmy Carter wrote, "Desmond Ball's counsel and cautionary advice based on deep research made a great difference to our collective goal of avoiding nuclear war".

Years later, and now battling cancer, Professor Ball's attention is focused on Asia and particularly along the volatile Thai-Burma border, where for the past 18 years, he's become a familiar figure amongst Burma's huge ethnic minority.

ROB O'NEILL, STRATEGIC POLICY INSTITUTE, SYDNEY UNI.: A lot of academics do get out and do field work, but not many get out into areas where they know they're going to get shot at and they're going to have people coming after them who want them dead.

MATT PEACOCK: Journalist Phil Thornton was inside Burma with the Karen Army when he first heard of Des Ball.

PHIL THORNTON: I'd taken a bit of respite from the sun in a signet intelligence office, if you like, a little bamboo hut, and there were some notes there - it was an extract from one of his books, signet intelligence books.

DES BALL: On that occasion, when Phil had gone into that shack, in fact we have just been working with a group of snipers in terms of training them on how to utilise radio intercepts for direct operational purposes.

MATT PEACOCK: A series of atrocities by Burmese Government-backed forces prompted Professor Ball's closer involvement with the KNLA.

DES BALL: A couple of particular guys were involved in taking large numbers of young girls, raping them, mutilating them, and when they'd finished with them, putting them in the bark and thatch huts and then burning the huts - burning the girls alive or just machine-gunning them. I was very uncomfortable with all of that and thought, "I just can't go home and forget about this. I should be doing something." So I took my contacts with the armed groups another step forward in terms of working out operational techniques for in fact tracking down and getting rid of these guys.

MATT PEACOCK: Ball enhanced the security of Karen communications as well as boosting its capacity to intercept enemy transmissions.

DES BALL: I'd been paying for a few radio sets, for example, just out of my own pocket, which I've continued to do ever since, and we were able to use those to really build up the whole radio interception side of the business.

MATT PEACOCK: While the world's welcomed the recent release of Burmese Opposition Leader Aung San Suu Kyi and other democratic reforms, Des Ball warns that for some ethnic Burmese, the situation's become worse. Wholesale land grabs for mineral and plantation wealth are what are now driving the military's actions.

DES BALL: We've seen in the last couple of years the first use of helicopter gunships against villages. We've seen the first use of jet fighter aircraft launching missiles against villages.

MATT PEACOCK: This might well be Des Ball's final battle, but he has no doubt that he's on the right side.

DES BALL: I've done things which do go well beyond what is done by a normal academic, but there is nothing there that I believe has been wrong and there's nothing there that I regret.

SARAH FERGUSON: Matt Peacock reporting.