Fewer than 10,000 strong, the Army Special Forces -- the Green Berets -- make up for their scarcity by subjecting their recruits to rigorous training, both physical and intellectual. (For one thing, they are expected to learn foreign languages.) The Special Forces were founded in 1952, U.S. News & World Report writer Linda Robinson explains, as successors to the paramilitary units of the Office of Strategic Services, whose mission had been to parachute behind enemy lines and fight alongside resistance groups in World War II. The current era of terrorism demands precisely what the Green Berets have to offer -- smarts, flexibility and expertise in unconventional warfare -- and Robinson's Masters of Chaos: The Secret History of the Special Forces (PublicAffairs, $26.95) showcases their activities since the attacks of Sept. 11, 2001.

Fresh from contributing to the U.S.-led overthrow of the Taliban in Afghanistan, the Special Forces were asked to take leading roles in assaults on Iraq in the spring of 2003. Forces operating in central Iraq, Robinson reports, "developed a method to deal with Iraq's ubiquitous walled compounds. They crouched on the roofs of their Humvees and, when they reached their destinations, they simply jumped off over the wall and into the compound. It saved them the time and trouble of breaking down the door."

A matter as simple as grooming can assume strategic weight. Immersed in Kurdish Iraq, one Special Forces group "adopted the native dress of the shamag scarves and the ballooning brown pants that were the uniform of the Kurdish pesh merga fighters. The soldiers grew mustaches. . . ; the pesh merga . . . are less inclined to respect the advice or follow the orders of clean-shaven men." Another commander, in a different sector, took a different tack: "He kept [his men] in army uniforms and regulation hair cuts. He . . . wanted to make them seem as big, American, and intimidating as possible to the Iraqi divisions."

-- Dennis Drabelle