Last month, Mr Lee Ellis stood in front of the infamous Hoa Loa Prison in Hanoi, overcome by a maelstrom of emotions.
The place holds dark memories for the war veteran. As an American fighter pilot during the Vietnam War, he was tortured and imprisoned there for 51/2 years after his F-4C Phantom was shot down and he was captured on Nov 7, 1967.
His trip last month was the first time in 41 years that he had gone back to Vietnam, and to the place he calls the pits of hell.
As Mr Ellis, 70, and his wife were about to enter the premises - now a war museum - the authorities stopped him from bringing in his video camera because it "looked too professional".
Arguing that he had a letter allowing him to do so cut no ice with the staff. "It just set me off, and brought back all the fear and sense of oppression and control," he says.
Once he was inside the building, his discomfort grew. Many of the cells where prisoners of war (POWs) were tortured were gone. There were, instead, exhibits and pictures showing how well American soldiers were treated.
"I feel a lot of resentment because of the lies told. Every time a lie is told, it undermines freedom. You need truth for freedom to really exist," says Mr Ellis, who stopped over in Singapore after his Vietnam trip.
Although frustrating, he says, the trip reminded him that he has to persevere with what he has set out to do. "I probably understand the importance of truth and the danger of lies better than the average person, and I want to challenge others to live the truth."
Mr Ellis, now a leadership expert, has written several books on the subject. In his latest, Leading With Honor, he uses stories and anecdotes from his time at Hoa Loa to illustrate the importance of virtues such as conscience, courage, trust and honour for corporate leaders today.
Trim, alert and looking at least a decade younger, the engaging septuagenarian says he was bent on becoming a fighter pilot from the age of five after seeing a World War II fighter plane in a park.
The younger of two sons of a food service manager and his science teacher wife, he grew up on a remote farm in North Georgia and learnt to be independent at a young age.
"I took care of the hogs, chopped wood for the fires, worked in the fields," recalls Mr Ellis, who ordered his first rifle by post for US$9.33 when he was 11. "When I was 14 or 15, I would sometimes take my shotgun and shoot two or three quail for dinner."
At the University of Georgia, he enrolled in the Air Force Reserve Officers' Training Corps (AFROTC), a college-based programme for training commissioned officers of the United States Armed Forces.
"My mother wanted me to study medicine since her brother was a doctor, but the moment I got my pilot's licence, I switched my major from pre-med to history."
Upon graduation in 1965, he was selected as a Distinguished Graduate of AFROTC and commissioned as a Second Lieutenant in the US Air Force. "Three days later, I went to flight school and 53 weeks later, I got my wings as an airforce pilot. I went from ploughing a mule to flying a supersonic jet in less than five years," he says with a laugh.
The training - which included stints in survival schools near the Canadian border and in Florida - was rigorous. As soon as he was combat-trained, he was shipped off to Danang, located between Ho Chi Minh City and Hanoi in North Vietnam.
The dangers of war were not something he had thought about.
"When you're young, you feel invincible; you think you can do anything. Besides, fighter pilots are all adrenaline junkies," he says. That was despite the fact that nearly a third of the fighter pilots in the Vietnam War never made it home.
"At that time, the rule was that you had to fly for one year, or if you flew over North Vietnam, complete 100 missions before you could go home. Usually, you could fly 100 missions in nine or 10 months," he says.
He was 24 and on his 53rd mission when he was shot down. He and his co-pilot Ken Fisher were on a mission to bomb the guns which protected a strategic ferry when their F-4C Phantom jet was hit.
"I knew the airplane wasn't flying, the stick was stiff and there was smoke in the cockpit," he recalls. "If we stayed in the plane, we were going to die. The plane was going to hit the ground at 400 miles an hour."
They ejected. He could hear shooting on the ground as he was landing. "My mind went, 'Evade, evade, this is your worst nightmare.' There was no time to think, I was just doing," he recalls.
He scampered into a bomb crater not far from where he landed, and activated his radio to relay his bearings even as he saw figures darting from bush to bush.
Ironically, all he could think of was a scene from the war movie The Bridges At Toko Ri, in which actors Mickey Rooney and William Holden play pilots who land in a ditch after being shot down behind enemy lines, and are killed after a shootout with North Korean communists.
He was soon surrounded. "In survival training, we were taught that the guys who capture you were the least well trained to handle prisoners so that was your best time to escape. I took out my revolver and fired a tracer round above their heads just to scare them off," he recalls. "Any good cop would have shot me right on the spot."
Instead, his captors pointed their rifles at him.
"One of them pulled out something from his pocket; it had a picture of an American soldier on one side, and Vietnamese phonetics on the other. He read, 'Sherrender no die, sherrender no die. Hands up'."
Tied and stripped to his boxers, he was marched and bundled into the back of a truck.
The two-week trip to Hoa Loa, nicknamed by American soldiers as the Hanoi Hilton, was terrifying. On several occasions, some of his captors tried to kill him.
"We were also bombed three times on the way to Hanoi. I was in a foxhole, watching the bombs come down," says Mr Ellis, who also had to spend a couple of nights in bamboo cages with other captured American soldiers.
In Hoa Loa, he was put in a cell measuring about 2m square with three other POWs.
"We had six months of thin watery pumpkin soup with a piece of bread or a cup of rice. Sometimes, there would be a spoonful of pumpkin stew," he says. He remembers being hungry and cold, especially in the winter months.
Interrogations during which POWs were kicked and beaten were regular occurrences. As he was the youngest and a junior officer, he did not get it as badly as the more senior men.
"They would always go for the senior guys because they thought if they could break them, they could break the organisation. But our seniors told us, 'If you heard anything, it's because they tortured us until we could not resist any more. It's a lie; don't pay attention.'"
He soon found out what it felt like to have his will broken.
One day, after he refused to fill in a questionnaire, his interrogators shackled his feet and forced him to kneel with his arms over his head for the entire night.
Each time he moved to lower his arms or sit, he would be hammered, each beating more brutal than the last.
He succumbed the next morning, and filled in the questionnaire with wrong and misleading information.
"It was a terrible psychological and physical ordeal. Not being tough enough to do what I wanted to do was very shameful. I cried when I gave in. I felt I was a worthless soldier," he says.
Several POWs did not survive. "Some were tortured a lot; they went on a hunger strike, went too far and lost touch with all reality. They wouldn't trust us, wouldn't trust the enemy, wouldn't eat and just went crazy and died."
Mr Ellis' training and the steeliness of his seniors in Hoa Loa helped him through.
"Pilots are optimistic. We believe in the future, believe in solving problems and we believe that in the end, we will win because we are competitive.
"In the prison, I also believed God kept me alive for a purpose so I told myself I had to stay alive and go home."
To while away the time, he started learning German, polishing his French, memorising poems and solving maths problems by working out building costs for an imaginary farm in his head.
"I started out with a farm and 40 acres; one month later, I had the whole county," he says.
The torture stopped two years after he entered Hoa Loa.
"Ho Chi Minh died in the fall of 1969, and and they quit torturing a few weeks after that," he says, referring to the leader of the Viet Cong. "The last three years were live and let live. If I had to go through another two years of what happened earlier, I don't think I would have been able to come home as physically and mentally solid."
He and the other POWs spent a lot of that period "decompressing". He says: "We realised we had to get rid of our bitterness before we went home."
On March 14, 1973, he finally checked out of the Hanoi Hilton.
The ordeal had changed him. "I knew I could just about do anything I needed to do," he says.
He went back to the army. Over the next two decades, he held several positions - from flight instructor to chief of flight standardisation and evaluation to flying squadron commander - and retired as an air force colonel in 1990.
Since then, he has been devoting his time and career to an interest which had taken root when he was at Hoa Loa: the study and research of optimal human performance and leadership under difficult circumstances.
After working with a non-profit organisation to develop career assessment, he started a leadership consultancy in 1998.
Besides executive training, he now runs leadership schools and develops leadership assessment for outfits running the gamut from Fortune 500 companies to non-governmental organisations.
Asked if leaders are born or made, he says: "You can be born with leadership characteristics but leaders need to develop and continue to grow. And all leaders can get better. We all have things that hold us back from becoming good leaders - a mindset, a belief or a fear."
It takes courage to be a good leader, he says.
"It's what we need most today - the courage to do the right thing and to be who we really want to be," says Mr Ellis, who is married to a therapist. They have four children and six grandchildren.
Candidly, he admits that he has had to learn to admit to and work on his own failings - anger problems, verbal harshness and the tendency to keep a tight lid on his emotions. But he adds that he is the better for having done so.
"The reality is, we have choices; we can go this way or that way. Humility is the way of suffering, it's living life the hard way and making the hard choices and you need courage to do that. But in the long run, that's where the payoff is."
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