The largest militaries in the world have poured hundreds of millions of dollars into the study and advancement of 3D printing. Control of the supply chain is more important in the military than in any other sector. Moving manufacturing closer to the action is crucial from a strategic standpoint since it is costly and time-consuming to ship replacement parts from machine tooling hubs abroad. The armed forces have utilized 3D printers in the field from the US to Australia because they have long understood the possibilities of additive manufacturing.