Depending on your definition 26 years
World War 1 brought a series of technological advances that would change the way people live. For example, synthetic rubber was introduced and it dramatically changed the automotive industry. In medicine, the introduction of blood banks meant that it was now possible to store blood instead of having to directly transfer it from donor to recipient. Debridement, which is the removal of infected flesh in order to heal wounds, was also developed during this period.
This shifted the appliance of science into creations that would be used for mass consumption in order to improve the quality of living of people.
Guam, Texas, parts of mexico, cuba (for a bit), philipines until after ww2, puerto rica, us virgin islands and I think that's it
