[2] During World War II, the US Army began experiments with containers to ship supplies to the front lines.

Cargo was being delayed at ports due to the time required by break bulk loading and offloading of ships.

[3] After proving successful in Korea, the Transporter was developed into the Container Express (CONEX) box system in late 1952.

By 1967, over 100,000 more had been procured to support the escalation of the Vietnam War,[7][10] making this the world's first intercontinental application of intermodal containers.

[10] The term "CONEX" remains in common use in the US military to refer to the similar but larger ISO-standard shipping containers.