The 2009 TIME 100

Lance Corporal Brady (Goose) Gustafson and his 20 fellow Marines sensed trouble on July 21 as they crept into the Afghan village of Shewan and saw civilians drifting away. Moments later, a barrage of rocket-propelled grenades (RPGs) and machine-gun fire enveloped Gustafson's mine-resistant ambush-protected vehicle (MRAP) and its three trailing humvees. An RPG exploded inside his vehicle, the resulting blast searing his face as it rushed through the open turret where he was manning the machine gun. He started shooting at gun flashes from an estimated 100 Taliban, some only 20 yards away. Gustafson, 21, stood up for a better firing position but was instantly racked with pain. "I looked down, and a lot of my right leg wasn't there," he says. "I could see muscle and bone, and I was bleeding pretty hard." The RPG had taken out six inches of leg bones and flesh. Gustafson's booted right foot dangled uselessly, attached only by his leg's calf muscles.

The MRAP stopped. The driver, hit in the head by shrapnel, appeared to be dead. Enemy machine-gun fire kept most of the other Marines inside their vehicles. Gustafson watched as his turret's bulletproof windows cracked under the onslaught. Somebody had to fire back. A Marine inside the MRAP yanked a tourniquet off his flak jacket and wound it tightly around Gustafson's shattered leg.

His wound stanched, Gustafson finished firing off the ammo belt's 200 rounds, pausing between each six-round burst to keep the barrel from melting. He pulled up and fired off another 17-lb. belt. After nearly 10 minutes, weak from blood loss, he swapped places; the other Marine kept firing as their driver came to and they escaped.

Gustafson now has a fake lower right leg and a real Navy Cross, the nation's second highest award, for valor. But the most important outcome, according to Gustafson: "We didn't lose a single Marine."

Fast Fact: To date, only 29 Navy Crosses have been awarded during the hostilities in Iraq and Afghanistan