Operation Diamond Arrow

Operation Diamond Arrow was a battle in southern Laos, waged from 20 September 1969 through 9 March 1970. The struggle centered on a Royal Lao Army stronghold at the strategic road intersection of Routes 16 and 23. Due to intervention by U.S. and Lao tactical air strikes, and an air bridge supply effort, the Royal Lao Army troops survived besiegement in a fixed defensive position, only to abandon their position post-battle.

Located in the southern panhandle of the territory of the Kingdom of Laos, the Ho Chi Minh Trail was the logistics backbone of the communist forces during the Second Indochina War, as it was the main supply route for Viet Cong and People's Army of Vietnam (PAVN) forces fighting in South Vietnam. During 1969, there were a number of military operations waged against the Trail in southern Laos, including Operation Maeng Da, Operation Honorable Dragon, and Operation Junction City Jr., that originated in Laos. Road intersections, such as the junction of Lao Routes 16 and 23 (since renumbered as Route 20), were prime objectives for both sides.

Operation Diamond Arrow was focused on Thatheng, where Routes 16 and 23 merged in an intersection to form Route 16/23. Surrounding mountainous terrain funneled traffic through this line of communication to the Bolovens Plateau. Occupation of the intersection was crucial to controlling the Plateau overlooking the Ho Chi Minh Trail. Some Royal Lao Army officers believed road closure by communist forces would lead to the Royal Lao Government's loss of the Bolovens Plateau.

In April 1969, a Royal Lao Army garrison abandoned Thateng to the enemy without any resistance. To counter the communist occupation of the town, Royalist troops were airlifted to a hilltop position overlooking the town and road intersection. On 20 September, a force of four Royalist companies of regulars and three of guerrillas launched Operation Diamond Arrow from Salavane, north of Thateng. Meeting only scattered opposition, this force reached Ban Toumlan on 8 October.

...
Wikipedia