Col. Hackworth urged military leaders to adopt his unconventional methods, as outlined in his handbook on guerrilla warfare, "The Vietnam Primer." They did not follow his advice.
On June 27, 1971, he appeared on ABC's "Issues and Answers" and savaged U.S. commanders in Vietnam, their strategies and their tactics. Branding Vietnam "a bad war," he declared that it couldn't be won and that the United States ought to get out.
U.S. Army Col. David H. Hackworth, shown in a 1971 photo, was forced to resign after calling Vietnam a bad war that couldn't be won.
Although antiwar forces hailed him as a hero, the military considered his comments tantamount to treason. He was forced to resign from the Army before he could be court-martialed or, as he maintained in his memoir, assassinated. He gave up his medals in protest and retired to a duck farm in Queensland, Australia, "the farthest place I could find from the United States and still speak English," he wrote in "About Face."
Reviewer Rick Atkinson, writing in The Washington Post's Book World, found much to like about the book. "Paradoxically, one of the strengths of the book is a warts-and-all candor through which we see much to dislike about David Hackworth," he wrote. "Often crude and truculent, he seems to spend an inordinate amount of time knocking people down with his fists."
Col. Hackworth stayed in Australia for 18 years, investing in real estate enterprises, running a popular restaurant in Brisbane and writing "About Face," which concludes with critiques of America's "total fiascos" in Iran, when a military team failed to rescue several American hostages, and in Grenada, where Marine and Army forces suffered 10 percent losses in the 1983 invasion.
He returned to the United States in 1989 to marry Eilhys England, who became his business and writing partner. From 1990 to 1996, he was a contributing editor for defense at Newsweek, covering the Persian Gulf War as well as peacekeeping operations in Somalia, the Balkans, Korea and Haiti.
He also wrote three more books -- "Hazardous Duty" (1996), a volume of war dispatches; "The Price of Honor" (1999), a novel about a corrupt U.S. military establishment; and "Steel My Soldiers' Hearts: The Hopeless to Hardcore Transformation of U.S. Army, 4th Battalion, 39th Infantry, Vietnam" (2002), written with his wife.
As a syndicated columnist for King Features, he often spoke out on behalf of the troops on the ground in harm's way. He wrote repeatedly about the danger of lightly armored Humvees and what he considered the absurdity of the Pentagon's inability or unwillingness to safeguard the troops.
"Our modern generals might give a lot of lip service to protecting the force, but any way you cut it, what's going on in Iraq is criminal," he wrote in a June 2004 column.
He ignited a national debate last year when he reported that Rumsfeld used a machine to sign condolence letters sent to the families of soldiers who lost their lives in Iraq. Rumsfeld later promised to sign each letter by hand.
Recently, he and his wife had been pushing for legal action to compel the Pentagon to recognize the Vietnam-era defoliant Agent Blue as a carcinogen on par with Agent Orange. He believed his fatal illness was caused by exposure to the defoliants.
Col. Hackworth's first two marriages, to Patricia Leonard and to Peter Margaret Cox, ended in divorce.
In addition to his wife, of Greenwich, Conn., survivors include three children from his first marriage, one child from his second marriage and a stepdaughter.