Author(s)

Kenneth R. Olson^1*, David R. Speidel^2#

¹College of Agricultural, Consumer, and Environmental Sciences, University of Illinois, Urbana, USA.
²Natural Resource Conservation Service and Foreign Agricultural Service, Benton, Missouri, USA.

In 1959, the United States Central Intelligence Agency (CIA) operation, against the Pathet Lao insurgences and Viet Mien military troops and supply route, began. The Ho Chi Minh Trail was developed after the North Vietnam government and military decided to reunify South and North Vietnam. The People’s Army of Vietnam (PAVN) then connected the old trails leading from North Vietnam panhandle southward into eastern Laos, Cambodia and South Vietnam. Starting from Hanoi, the primary trail turned southwest into Laos and eastern Cambodia before branching into South Vietnam. Beginning in 1960s, the volume of traffic on the network of trails expanded significantly, but it still took more than a month’s march, by foot and bicycle, to travel from North to South Vietnam. Ho Chi Minh Trail traffic was impacted repeatedly by Royal Laotian Air Force (RLAF), which was supported by US Air Force tactical herbicide spraying (Operation Ranch Hand program), and US Air Force bombing runs. By the late 1960s, the trail was improved and could accommodate heavy trucks in some sections and was used to supply the annual needs of over one hundred thousand regular PAVN troops active in South Vietnam. By 1974, the trail was a well-marked series of jungle roads (some of them paved) with underground support facilities such as hospitals, fuel-storage tanks, and supply caches with weapons. The Ho Chi Minh Trail was the major supply route for PAVN forces that overran Republic of Vietnam (RVN) forces in 1975 and unified Vietnam. The primary objective of this paper is to determine the environmental impacts of RLAF and US Air Force secret spraying of tactical herbicides on Ho Chi Minh Trail in Laos.

Ho Chi Minh Trail, Laos, Cambodia, North Vietnam, South Vietnam, Agent Orange, Agent Blue, Dioxin TCDD, Arsenic, Cloud Seeding, Mud Making

Olson, K. and Speidel, D. (2023) United States Secret War in Laos: Long-Term Environmental Impacts of the Use of Chemical Weapons. Open Journal of Soil Science, 13, 199-232. doi: 10.4236/ojss.2023.134009.