Hovering U.S. Army helicopters pour machine gun fire into a tree line to cover the advance of South Vietnamese ground troops in an attack on a Viet Cong camp 18 miles north of Tay Ninh, near the Cambodian border, in March of 1965. #

An American officer serving with the South Vietnam forces poses with group of Montagnards in front of one of their provisionary huts in a military camp in central Vietnam on November 17, 1962. They were brought in by government troops from a village where they were used as labor force by communist Viet Cong forces. The Montagnards, dark-skinned tribesmen numbering about 700,000, live in the highlands of central Vietnam. The government was trying to win their alliance in its war with the Viet Cong. #

Vietnamese airborne rangers, their two U.S. advisers, and a team of 12 U.S. Special Forces troops set out to raid a Viet Cong supply base 62 miles northwest of Saigon, on August 6, 1963. As the H-21 helicopters hovered six feet from the ground to avoid spikes and wires and under sniper fire, the troops jumped out to attack. #

A South Vietnamese Marine, severely wounded in a Viet Cong ambush, is comforted by a comrade in a sugar-cane field at Duc Hoa, about 12 miles from Saigon, on August 5, 1963. A platoon of 30 Vietnamese Marines was searching for communist guerrillas when a long burst of automatic fire killed one Marine and wounded four others. #

Napalm air strikes raise clouds into gray monsoon skies as houseboats glide down the Perfume River toward Hue in Vietnam on February 28, 1963, where a battle for control of the old Imperial City ended with a Communist defeat. Firebombs were directed against a village on the outskirts of Hue. #

Thich Quang Duc, a Buddhist monk, burns himself to death on a Saigon street on June 11, 1963, to protest alleged persecution of Buddhists by the South Vietnamese government. President Ngo Dình Diem, part of the Catholic minority, had adopted policies that discriminated against Buddhists and gave high favor to Catholics. #

Flying low over the jungle, an A-1 Skyraider drops 500-pound bombs on a Viet Cong position below as smoke rises from a previous pass at the target, on December 26, 1964. #

Partially covered, a dying Viet Cong guerrilla raises his hands as South Vietnamese Marines search palm groves near Long Binh in the Mekong Delta, on February 27, 1964. The guerrilla died in a foxhole following a battle between a battalion of South Vietnamese Marines and a unit of Viet Cong. #

As U.S. "Eagle Flight" helicopters hover overhead, South Vietnamese troops wade through a rice paddy in Long An province during operations against Viet Cong guerrillas in the Mekong Delta, in December of 1964. The "Eagle Flight" choppers were loaded with Vietnamese airborne troops who were dropped in to support ground forces at the first sign of enemy contact. #

A father holds the body of his child as South Vietnamese Army Rangers look down from their armored vehicle on March 19, 1964. The child was killed as government forces pursued guerrillas into a village near the Cambodian border. #

With the persuasion of a Viet Cong-made spear pressed against his throat, a captured Viet Cong guerrilla decided to talk to interrogators, telling them of a cache of Chinese grenades on March 28, 1965. He was captured with 13 other guerrillas and 17 suspects when two Vietnamese battalions overran a Viet Cong camp about 15 miles southwest of Da Nang air force base. #

Thousands attend a rally on the grounds of the Washington Monument in Washington on April 17, 1965, to hear Ernest Gruening, a Democratic senator from Alaska, and other speakers discuss U.S. policy in Vietnam. The rally followed picketing of the White House by students demanding an end to Vietnam fighting. #

A nurse attempts to comfort a wounded U.S. Army soldier in a ward of the 8th army hospital at Nha Trang in South Vietnam on February 7, 1965. The soldier was one of more than 100 who were wounded during Viet Cong attacks on two U.S. military compounds at Pleiku, 240 miles north of Saigon. Seven Americans were killed in the attacks. #

Flag-draped coffins of eight American Servicemen killed in attacks on U.S. military installations in South Vietnam, on February 7, are placed in transport plane at Saigon, February 9, 1965, for return flight to the United States. Funeral services were held at the Saigon Airport with U.S. Ambassador Maxwell D. Taylor and Vietnamese officials attending. #

Injured Vietnamese receive aid as they lie on the street after a bomb explosion outside the U.S. embassy in Saigon, Vietnam, on March 30, 1965. Smoke rises from wreckage in background. At least two Americans and several Vietnamese were killed in the bombing. #

Four "Ranch Hand" C-123 aircraft spray liquid defoliant on a suspected Viet Cong position in South Vietnam in September of 1965. The four specially equipped planes covered a 1,000-foot-wide swath in each pass over the dense vegetation. #

A strategic air command B-52 bomber with externally mounted, 750-pound bombs heads toward its target about 56 miles northwest of Saigon near Tay Ninh on November 2, 1965. #

General William Westmoreland talks with troops of first battalion, 16th regiment of 2nd brigade of U.S. First Division at their positions near Bien Hoa in Vietnam, in 1965. #

Flares from planes light a field covered with the dead and wounded of the ambushed battalion of the U.S. 1st Cavalry Division in the Ia Drang Valley, Vietnam, on November 18, 1965, during a fierce battle that had been raging for days. Units of the division were battling to hold their lines against what was estimated to be a regiment of North Vietnamese soldiers. Bodies of the slain soldiers were carried to this clearing with their gear to await evacuation by helicopter. #

A U.S. Marine, newly arrived in South Vietnam on April 29, 1965, drips with perspiration while on patrol in search of Viet Cong guerrillas near Da Nang air base. American troops found 100-degree temperatures a tough part of the job. General Wallace M. Greene Jr., a Marine Corps commandant, after a visit to the area, authorized light short-sleeved uniforms as aid to troops’ comfort. #

A Vietnamese litter bearer wears a face mask to keep out the smell as he passes the bodies of U.S. and Vietnamese soldiers killed in fighting against the Viet Cong at the Michelin rubber plantation, about 45 miles northeast of Saigon, on November 27, 1965. #

Wounded and shocked civilian survivors of Dong Xoai crawl out of a fort bunker on June 6, 1965, where they survived murderous ground fighting and air bombardments of the previous two days. #

A Vietnamese girl, 23 years old, was captured by an Australian patrol 30 feet below ground at the end of a maze of tunnels some 10 miles west of the headquarters of the Australian task force (40 miles southeast of Saigon). The woman was crouched over a World War II radio set. About seven male Viet Cong took off when the Australians appeared—but the woman remained and appeared to be trying to conceal the radio set. She was taken back to the Australian headquarters where she told under sharp interrogation (which included a "waterprobe"; see her wet clothes after the interrogation) that she worked as a Viet Cong nurse in the village of Hoa Long and had been in the tunnel for 10 days. The Australians did not believe her because she seemed to lack any medical knowledge. They thought that she may have possibly been the leader of the political cell in Long Hoa. She was being led away after interrogation, clothes soaked from the "waterprobe" on October 29, 1966. #

Left: Pilot Leslie R. Leavoy in flight with other jets in the background above Vietnam in 1966. Right: Army nurse 2nd Lieutenant Roberta “Bertie” Steele in South Vietnam, on February 9, 1966. #

Women and children crouch in a muddy canal as they take cover from intense Viet Cong fire at Bao Trai, about 20 miles west of Saigon, on January 1, 1966. Paratroopers, background, of the U.S. 173rd Airborne Brigade escorted the South Vietnamese civilians through a series of firefights during the U.S. assault on a Viet Cong stronghold. #

A Marine, top, wounded slightly when his face was creased by an enemy bullet, pours water into the mouth of a fellow Marine suffering from heat during Operation Hastings along the demilitarized zone between North and South Vietnam on July 21, 1966. #

Left: A Vietnamese child clings to his bound father who was rounded up as a suspected Viet Cong guerrilla during “Operation Eagle Claw” in the Bong Son area, 280 miles northeast of Saigon on February 17, 1966. The father was taken to an interrogation camp with other suspects rounded up by the U.S. 1st air cavalry division. Right: The body of an American paratrooper killed in action in the jungle near the Cambodian border is raised up to an evacuation helicopter in War Zone C, Vietnam, in 1966. #

The singing group the "Korean Kittens" appear on stage at Cu Chi, Vietnam, during the Bob Hope USO Christmas show, to entertain U.S. troops of the 25th Infantry Division. #

A grim-faced U.S. Marine fires his M60 machine gun, concealed behind logs and resting in a shallow hole, during the battle against North Vietnamese regulars for Hill 484, just south of the demilitarized zone, on October 10, 1966. After three weeks of bitter fighting, the 3rd battalion of the 4th Marines took the hill the week of October 2. #

Lieutenant Commander Donald D. Sheppard, of Coronado, California, aims a flaming arrow at a bamboo hut concealing a fortified Viet Cong bunker on the banks of the Bassac River, Vietnam, on December 8, 1967. #

A U.S. Marine CH-46 Sea Knight helicopter comes down in flames after being hit by enemy ground fire during Operation Hastings, just south of the demilitarized zone between North and South Vietnam, on July 15, 1966. The helicopter crashed and exploded on a hill, killing one crewman and 12 Marines. Three crewmen escaped with serious burns. #

A trooper of the U.S. 1st cavalry division aims a flamethrower at the mouth of cave in An Lao Valley in South Vietnam, on April 14, 1967, after the Viet Cong group hiding in it were warned to emerge. #

Sergeant Ronald Payne, 21, of Atlanta, Georgia, emerges from a Viet Cong tunnel holding his silencer-equipped revolver with which he fired at guerrillas fleeing ahead of him underground. Payne and others of the 196th light infantry brigade probed the massive tunnel in Hobo Woods, South Vietnam, on January 21, 1967, and found detailed maps and plans of the enemy. The infantrymen who explored the complex are known as “Tunnel Rats.” They were called out of the tunnels on January 21, and nauseating gas was pumped in. #

Military police, reinforced by Army troops, throw back anti-war demonstrators as they tried to storm a mall entrance doorway at the Pentagon in Washington, D.C., on October 21, 1967. #

U.S. Navy Douglas A-4E Skyhawks from Attack Squadrons VA-163 Saints and VA-164 Ghost Riders attack the Phuong Dinh railroad bypass bridge, 10 kilometers north of Thanh Hoe, North Vietnam, on September 10, 1967. Note the attacking Skyhawk in the lower right and one directly left of the explosions on the bridge. #

U.S. soldiers of the 3rd Brigade, 4th Infantry Division, look on a mass grave of enemy combatants after a day-long battle against the Viet Cong 272nd Regiment, about 60 miles northwest of Saigon, in March of 1967. U.S. military command reported 423 Communist forces dead, with American losses at 30 dead, 109 wounded, and three missing. #