McNamara Line
Named after Secretary of Defense Robert McNamara, the McNamara line was an electronic infiltration barrier that was originally designed to stretch across Vietnam and Laos. Construction of the Vietnam section (Dye Marker) began in 1967, but was cancelled after the much of the equipment was commandeered for the defense of the
Khe Sanh Marine base in January 1968. However, the Laos portion (Muscle Shoals) was completed and its acoustic and seismic sensors were successfully used to identify bomb targets on the
Ho Chi Minh Trail.
See
Igloo White