Which method Marines had to develop to achieve speed and dispersion on a potentially atomic battlefield?

To achieve speed and dispersion on a potentially atomic battlefield, Marines developed the "Vertical Envelopment" method, which emphasizes rapid deployment and maneuverability. This approach allows for the use of helicopters and other aircraft to transport troops and supplies quickly, enabling them to bypass heavily defended enemy positions. The focus on decentralized operations and flexible tactics enhances their ability to adapt to the chaotic conditions of a nuclear threat environment.