My Lai massacre hero dies at 62
It was 30 years before the US military honoured Thompson (left)
Mr Thompson and his crew came upon US troops killing civilians at the village of My Lai on 16 March 1968.
He put his helicopter down between the soldiers and villagers, ordering his men to shoot their fellow Americans if they attacked the civilians.
"There was no way I could turn my back on them," he later said of the victims.
Mr Thompson, a warrant officer at the time, called in support from other US helicopters, and together they airlifted at least nine Vietnamese civilians - including a wounded boy - to safety.
He returned to headquarters, angrily telling his commanders what he had seen. They ordered soldiers in the area to stop shooting.
But Mr Thompson was shunned for years by fellow soldiers, received death threats, and was once told by a congressman that he was the only American who should be punished over My Lai.
A platoon commander, Lt William Calley, was later court-martialed and sentenced to life in prison for his role in the killings.
President Richard Nixon commuted his sentence to three years' house arrest.
Although the My Lai massacre became one of the best-known atrocities of the war - with journalist Seymour Hersh winning a Pulitzer Prize for reporting on it - little was known about Mr Thompson's actions for decades.
In the 1980s, Clemson University Professor David Egan saw him interviewed in a documentary and began to campaign on his behalf.
He persuaded people including Vietnam-era Secretary of State Dean Rusk to lobby the government to honour the helicopter crew.
Mr Thompson and his colleagues Lawrence Colburn and Glenn Andreotta were awarded the Soldier's Medal, the highest US miltiary award for bravery when not confronting an enemy.
Mr Thompson was close to tears as he accepted the award in 1998 "for all the men who served their country with honour on the battlefields of South-East Asia".
Mr Andreotta's award was posthumous. He was killed in Vietnam less than a month after My Lai.
Mr Colburn was at Mr Thompson's bedside when he died, the Associated Press reported.Mr Thompson died of cancer. He had been ill for some time and was removed from life support earlier in the week.
How many heroic and honorable men and women of African descent never get the praise they deserve?
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