Space Doctrine Publication 4-0 Sustainment : Nimble Books : 9781608882168 : 1608882160 : 05 Dec 2023 : Militaries, governments, economies, and societies in the US and all over the world rely heavily on services provided via space systems. With a few exceptions, the world is designed around the assumption that space services will always be available. Even though it is understood that space systems may be quite vulnerable to disruption, no one is really ready for prolonged or severe down times. Space Force's sustainment mission is all about maximizing "up time" under all circumstances. This document, titled "Space Doctrine Publication 4-0, Sustainment," provides guidance and principles for the proper use of military spacepower in support of the United States Space Force's responsibilities. It covers topics such as the operational environment, fundamentals of sustainment, sustainment capabilities, and roles and responsibilities of organizations involved in space operations. The docume