David Hackworth: In June 1971 Col David Hackworth, probably America's most decorated soldier in Vietnam, appeared on ABC television and told his countrymen that the war could not be won, that US military leaders had failed to understand or train their men for the nature of the country or the conflict, that Saigon would fall to the communists within five years and that one of every five American casualties had been the victim of so-called friendly fire.
This criticism put Hackworth, who has died aged 73, under concerted attack from his superiors, an assault made easier to sustain by the fast and loose approach to regulations he had employed as commander of a Blackhawk air cavalry brigade in Vietnam.
His troops wore Civil War hats, and Hackworth, as commander of the unit, later became the model for Col Kilgore, the abrasive, cigar-chomping officer played by Robert Duvall in the 1979 film Apocalypse Now.
Hackworth had set up his unit's own bordello in Vietnam, and the US army used that and other violations to threaten him with court-martial. However, Gen Creighton Abrams, the overall commander in Vietnam, called him "the best battalion commander I ever saw", and in 1971 he was allowed to resign with an honourable discharge.
He threw away his medals in protest and moved to Australia.
In the 1980s Hackworth returned to the US after his medals were reissued, and his book about Vietnam, About Face, became a best-seller. From 1990 to 1996 he was a contributing editor on defence at Newsweek magazine, where he wrote a column revealing that Admiral Michael Boorda, a former chief of US naval operations, wore combat medals he had not earned.
When the admiral committed suicide, Hackworth again incurred the military's wrath. He was accused of lying when he claimed to be the army's "most-decorated soldier" - the US keeps no statistics on such matters - and of wearing an unearned Ranger tab.
An army investigation found that Hackworth had been issued with the tag in error, but had never been given a number of medals he had earned. His decorations included two Distinguished Service Crosses, the second-highest US award for valour, 10 Silver Stars, eight Bronze Stars and eight Purple Hearts.
After leaving Newsweek, Hackworth wrote a syndicated newspaper column, Defending America, with his third wife, Eilhys England. Covering both Iraq wars and peacekeeping actions in Somalia, the Balkans and Haiti, he became a fierce critic of the US establishment.
His website, Soldiers for Truth, lambasted the Pentagon's "perfumed princes", who he claimed constantly betrayed the ordinary soldier. He was particularly incensed that Donald Rumsfeld used a machine to sign condolence letters sent to the families of dead soldiers in Iraq.
Hackworth's army connections began young. Orphaned at five months and raised by his grandmother in Santa Monica, California, he shined shoes at a local army base, becoming a mascot to the soldiers, who gave him his own uniform. At 14 he lied about his age and joined the US merchant marine; a year later he paid a sailor to impersonate his father and get him into the army, where he served in postwar Italy, policing the border dispute over Trieste.
He won his first Silver Star in Korea at the age of 20, when his battlefield commission made him the army's youngest captain. Commanding the Wolfhound Raiders, he led one attack despite being shot in the head, modelling himself on James Gavin, America's youngest second World War general (played by Ryan O'Neal in the 1977 film, A Bridge Too Far).
Hackworth volunteered for service with the US special forces in Vietnam and, as the army's youngest full colonel, returned in 1965, commanding a paratroop unit.
With Gen SLA "Slam" Marshall, he wrote the Vietnam Primer, a guide to counterguerrilla tactics. He used his theories about the enemy, whom he referred to as "the G", to transform a hapless 4/39 infantry unit into what became known as the Hardcore Battalion, driving his men so hard they allegedly put a cash bounty on him.
But he also won their loyalty, by such acts as leading the rescue of a trapped company while riding on the strut of a helicopter. It was one of three times on which Hackworth was nominated for the Congressional Medal of Honour, the US's highest award.
After leaving the army he was successful in property and restaurants in Brisbane and became active in the Australian peace movement. He returned to Greenwich, Connecticut, in the 1980s.
Hackworth's many books included a novel, Price of Honor, a volume of war dispatches, Hazardous Duty, and a memoir of the Hardcore Battalion, Steel My Soldier's Hearts. Serving soldiers fed his website with information about the army's leadership shortcomings. Last February he wrote: "Most combat vets pick their fights carefully. They look at their scars, remember the madness and are always mindful of the fallout . . . the White House and the Pentagon are run by civilians who have never sweated it out on a battlefield."
Hackworth died in Tijuana, Mexico, while pursuing alternative treatments for bladder cancer, a common cause of death among soldiers exposed to the dioxins Agent Orange and Agent Blue, used to defoliate Vietnam.
He is survived by Eilhys and his stepdaughter, two daughters and a son from his first marriage and a son from his second marriage.
David Haskell Hackworth: born November 11th, 1931; died May 4th, 2005