Declassified CIA Files Reveal Cold War Weather Modification Programs

Another program, Project Popeye, became one of the most controversial weather modification efforts in U.S

Beginning in 1967 during the Vietnam War, the U. S. military conducted cloud-seeding operations intended to extend monsoon conditions over enemy supply routes, particularly along the Ho Chi Minh Trail.

The objective was to increase rainfall, create mudslides, and disrupt troop and supply movements.