David Hackworth, who died of cancer Wednesday at a clinic in Tijuana, Mexico, at age 74, was a much-decorated military man who became a journalist and television commentator after quitting the Army in 1971 in disgust over its tactics in Vietnam.

The youngest Army captain in Korea, the youngest colonel in Vietnam, and the author of the “Veteran Primer,” a manual on counterinsurgency for the Army, Hackworth was a born warrior who was injured eight times in a 25-year military career.

A familiar figure on the Fox News Channel in recent years, Hackworth was a relentless critic of military brass, whom he referred to as “Perfumed Princes.” He criticized tactics used in the Iraq war, saying they reflected outmoded thinking, and he advocated for soldiers in the field. He used his Web site and syndicated column to ventilate complaints about inadequate equipment and supplies, often reproducing verbatim examples from the hundreds of servicemen’s emails he received each day.

Hackworth’s abrasive style made him plenty of enemies in the Pentagon. Preliminary court-martial proceedings were brought against him in 1971 after he went on national TV to say, “This is a bad war. … It can’t be won. We need to get out.” Instead, he was allowed to resign and was honorably discharged. In a later autobiography, “About Face,” Hackworth admitted that the charges, which included taking drugs with his men and setting up a brothel at his base in Vietnam, were true.

Disillusioned and war-weary, Hackworth moved to Australia, where he raised ducks, became a wealthy restaurateur, and managed to become an outspoken anti-nuclear advocate.

After returning to promote his memoir, in 1989, he decided to move back to America, and eventually became a contributing editor for defense for Newsweek in time to cover the first Gulf War. His 1996 investigation of Admiral Jeremy Boorda’s apparent fraud in wearing unauthorized military decorations led to the admiral’s suicide. The imbroglio later boomeranged bizarrely, as it was alleged that Hackworth – never shy about advertising himself as the Army’s most decorated soldier – was also displaying unauthorized decorations. A subsequent Army audit essentially cleared him of wrongdoing, but not before he lost his job at Newsweek.

Upon meeting him in the ruins of a base camp in Vietnam’s Central Highlands, writer Ward Just described him as “compact, with forearms the size of hams. His uniform was filthy and his use of obscenity was truly inventive.” Hackworth – universally known as Hack – seemed to have been born to play a war hero like himself. He was born on Armistice Day, 1930, and liked to remind interviewers that it was a birthday he shared with General Patton. He was orphaned at age 1 when his parents – his father was a miner – died within weeks of each other. He spent four years in an orphanage, and then was rescued by his grandmother, who raised him near a military base in Santa Monica, Calif.

When Hackworth turned 15, he wanted to enlist in the Armed Forces, so he paid a derelict to impersonate his father. After serving a year in the Merchant Marine, he joined the Army in the waning days of World War II and seems to have felt like he finally was among family. His first appearance in the news came in 1948, when he was involved in a bar fight in Venice, Italy, in which two Italians were shot dead by his buddy. (The buddy was Corporal Ernest Medina, later notorious as the commander on the ground during the My Lai massacre, an atrocity Hackworth attributed to lax command.)

Hackworth subsequently was deployed to Korea, where he developed a reputation as an inventive commander. During one battle over a numbered hilltop, his unit battered, Hackworth ordered his men to capture a live soldier. The prisoner disclosed that Chinese morale was low, and Hackworth ordered his men to storm the hilltop, successfully. At another point, Hackworth’s unit was cleaning up a battlefield when he stepped on a mine. Partially deafened by a previous injury, he didn’t hear the tripwire click, but his men did, and dove to safety. The mine went off, but, miraculously, Hackworth was unharmed. He quickly began barking orders at his men, then sneaked away to “go into shock in private.”

After various peacetime appointments, Hackworth was deployed to Vietnam in 1965. After a brief survey, he produced the “Veteran Primer,” his recipe for “out-geeing the G,” G being his shorthand for guerrilla.

His proudest achievement, he later wrote, was transforming the 4/39 infantry battalion, widely considered a bunch of hopeless losers, into the “Hardcore Battalion,” an outfit of extremely effective killers. He once climbed onto the strut of a helicopter and landed on top of an enemy position to rescue elements of a company that were pinned down. He later justified drinking and smoking with enlisted men, living with a woman not his wife, setting up a brothel, and dealing on the black market as measures meant to preserve his men’s health and morale. It was said that this rogue period was the basis for Marlon Brando’s portrayal of Colonel Kurtz in “Apocalypse Now.”

In addition to “About Face,” Hackworth produced a compilation of wartime journalism, “Hazardous Duty” (1996), as well as “Steel My Soldiers’ Hearts” (2002), about the Hardcore Battalion, and a novel about Vietnam, “The Price of Honor” (1999). He founded the organization Soldiers for the Truth to rally for military reform.

A hallmark of his work was the fear that the Army had learned little from combat in Vietnam and elsewhere. He placed the blame squarely on the brass, starting with the secretary of defense, Donald Rumsfeld, whom he repeatedly described in the harshest language.

In an interview with Salon.com in 2003, Hackworth said, “America has never been capable of fighting the G; from [General] Custer who f– it up, you can fast forward to today. [In Iraq] they are proving it again. The U.S. military never, never learns from the past. They make the same mistake over and over again.”

David Hackworth

Born November 11, 1930, outside Los Angeles; died May 4 in Tijuana, Mexico, of bladder cancer; survived by his wife, Eilhys England, four children from previous marriages, four grandchildren, and a stepdaughter. He is to be buried at Arlington National Cemetery.