On this day in 1968, the U.S. joint-service Operation Niagara is launched to support the U.S. Marine base at Khe Sanh. The Khe Sanh base was one of a series of bases that stretched across South Vietnam and they formed a strong defensive line, known as the Mc Namara Line, across much of the south of Vietnam in order to defend the main population centers such as Saigon from Communist attacks. Intelligence sources believed that North Vietnam was concentrating its forces in the Khe Sanh area.
It was clear that the communists were about to launch a major attack on Khe Sanh. If this key base was to fall to the communists it would have allowed the communists to advance further into the South and attack the major cities. In order to prevent this, the US and the South Vietnamese decided to launch Operation Niagara. This operation was a combined U.S. Air Force, Navy and Marine Corps air campaign that sought o provide close-air-support to the Marines who were defending Khe Sanh. This was essential as the communists had control of much of the countryside around Khe Sanh and they had all but encircled the base.
President Johnson ordered that the base must be held at all cost. The combined air campaign provided reconnaissance and gave vital information that allowed US units to target the North Vietnamese. The North Vietnamese besieged Khe Sanh and for 66 days they attacked the Marines holding it. As part of Operation Niagara, some 24,000 sorties flown. They bombed the North Vietnamese besieging the base day and night. For 66 days, it seemed that the North Vietnamese seemed on the verge of victory at Khe Sanh.
The Marines fought gallantly but they were also reliant on the air support. If it were not for the constant air-support the Marines may not have been able to resist the constant waves of communist attacks. The communists suffered heavy casualties as they attempted to capture the base. The Americans launched a ground offensive to break the siege of Khe Sanh and this eventually succeeded.
The relief of the fire base was proclaimed to be a major victory, even though the base was later dismantled. This was to make the end of the end of the McNamara Line strategy. No one can deny the importance of the air support provided by Operation Niagara in the victory of Khe Sanh. It is estimated that the aerial campaign dropped over 100,000 tons of explosives on the North Vietnamese and approximately 1,300 tons were dropped every day. They proved particularly effective in destroying communist mortar and artillery positions.