53 years ago, a vicious, unexpected attack showed Americans what kind of war they were really fighting in Vietnam

• In the final hours of January 1968, the Viet Cong and North Vietnamese Army launched a massive offensive across South Vietnam.
• The Tet Offensive failed to hold territory or spark a general uprising, but daily footage of brutal fighting broadcast into homes in the US had a profound effect on how Americans viewed the war.
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Shortly after midnight on January 30, 1968, cities in South Vietnam came under simultaneous attack by North Vietnamese Army (NVA) soldiers and Viet Cong (VC) guerrillas.

Many of the attacks were beaten back relatively quickly, some within hours, but the following days revealed that the fighting was not isolated.

Over 100 locations, including 36 of South Vietnam’s 44 provincial capitals, six of its largest cities, and dozens of towns, hamlets, and South Vietnamese Army (ARVN) and US bases faced a massive and well-coordinated attack.

The NVA and VC had launched their Tet Offensive, a brutal assault by some 84,000 soldiers and guerrillas across South Vietnam. They were told to “crack the sky” and “shake the earth” and that the offensive would be “the greatest battle ever fought in the history of our country.”

What ensued would change the course of the Vietnam War.

A plan to start an uprising

American military advisors had been on the ground in Vietnam for over a decade, but the country saw ever increasing fighting since the US directly intervened in 1965.

By 1968, at least 485,000 US troops were stationed in the country. The fighting on the ground was almost exclusively in the countryside, and bombing operations had expanded into Laos and Cambodia in an effort to destroy the Ho Chi Minh Trail, the main supply line for communist forces.

Contrary to statements made by President Lyndon B. Johnson and the overall US commander in Vietnam, Army Gen. William Westmoreland, there was no sign of victory in sight.

The war had entered a stalemate, and the leaders of North Vietnam, upset by the lack of progress, devised a plan that they believed would give them the decisive victory necessary to unify Vietnam under communism.

They would take the fight directly to South Vietnam's centers of power - the cities.

The objective was to take control of the major cities, broadcast messages of revolution, and start a general uprising across the country, overwhelming American and ARVN forces and leaving the US with no choice but to withdraw.

The offensive took place during Tet, a holiday that was traditionally, but unofficially, seen as a ceasefire period, allowing ARVN soldiers to return home.

In the months before the offensive, the NVA and VC smuggled thousands of men, weapons, and tons of supplies down the Ho Chi Minh trail and into South Vietnam's cities.

Diversion at Khe Sanh

By December, US and ARVN commanders knew something was coming. They noticed the massive increase in activity along the Ho Chi Minh trail, and captured reports showed plans for attacking cities. They also intercepted a recorded message calling on locals to rise up.

Westmoreland believed these were diversions and that the true target was Khe Sanh, a large military base just a few miles from the demilitarized zone between North and South Vietnam.

Worried that the US could suffer a defeat like France's disastrous loss at Dien Bien Phu 14 years earlier, Westmoreland ordered reinforcements to Khe Sanh and put its 6,000-strong Marine garrison on alert.

Sure enough, almost 20,000 NVA troops attacked Khe Sanh on January 21, starting a brutal months-long siege.

Believing this to be the main attack, the US threw a massive amount of firepower into the fight, dropping close to 100,000 tons of bombs on NVA positions. Half of the US Army's mobile reserve was also sent into the area.

But Khe Sanh was the diversion.

Saigon

A little more than a week after the fighting at Khe Sanh started, the true targets came under attack. Saigon, South Vietnam's capital, was the biggest.

Shortly after midnight, the presidential palace came under assault, as did the airport, the city's biggest radio station, and multiple bases, including Westmoreland's own headquarters.

Most shocking, 19 VC commandos breached the US Embassy, engaging US troops in a six-hour long firefight before being killed or captured.

But things fell apart for the VC and NVA in Saigon. US and ARVN forces inflicted massive casualties, and operators at the radio station prevented the call for an uprising from going out.

By early February, the attackers were on the defensive, and the fighting was over by early March.

Huế

As ARVN and American soldiers were regaining ground across the country, in Huế, near the northern border, the bloodiest battle of the offensive was only getting started.

Huế, the old imperial capital, was a major cultural, religious, and educational center. It was divided by the Perfume River: to the north was the walled-off old city within the 200-year-old citadel, and in the south was the city's new section.

On January 31, over 5,000 NVA and VC stormed the western walls, quickly taking all but two areas: the Mang Ca garrison in the northeast corner of the citadel, controlled by the ARVN 1st Division, and the MACV compound held by US Marines on the southeast corner in the new city.

An initial US attempt to link up with the ARVN was repulsed, and American troops, untrained in urban combat, fought floor by floor, house by house, and block by block for weeks.

The Americans were originally denied permission to use tanks or airstrikes, but the bans were lifted after it became clear how entrenched communist forces were.

By February 10, the Marines had killed 1,000 combatants and secured the new city at a cost of 358 casualties. They then linked up with the ARVN and pushed into the citadel, where the process started again.

Only after the communist forces' supply lines had been cut were the Marines and the ARVN able to secure the citadel. By February 25, the remaining NVA and VC had retreated, and the city was fully secured on March 2.

Aftermath

The Tet offensive was devastating.

Eighty percent of Huế was destroyed, and over 2,000 civilians there, labeled as threats to the revolution, were executed by VC death squads. Thousands of civilians were also killed in the fighting. US and South Vietnamese forces suffered over 12,000 casualties, including more than 2,600 deaths.

The offensive was also a disaster for North Vietnam. Of about 84,000 combatants, up to 58,000 are believed to have been killed, wounded, or captured. The VC was particularly hard hit, losing so many guerrillas that it was effectively wiped out as a viable fighting force.

In addition, they achieved none of their objectives. There was no general uprising, no South Vietnamese units defected, and they were unable to hold any of the cities or towns they seized.

But Tet was a strategic victory for the North.

Every day, media outlets broadcast graphic images of death and destruction directly into American homes. Particularly horrifying were images of the summary execution of a VC death squad captain by a South Vietnamese general.

Moreover, the fact that the NVA and VC had conducted such a large-scale attack as Johnson and Westmoreland promised victory was near led many Americans to see the war as unwinnable.

Political opinion turned against the war, and the US mission shifted to strengthening South Vietnam's military so it could fight alone, enabling the US to withdraw, which it did in 1973. But South Vietnamese forces were quickly overwhelmed, and Saigon fell in 1975.