The CO 2 emissions of the largest militaries are greater than many of the world’s countries combined. Military vehicles, aircraft, vessels, buildings and infrastructure all require energy, and more often than not that energy is oil, and energy efficiency is low. Maintaining military readiness means training, and training consumes resources. These might be common metals or rare earth elements, water or hydrocarbons. Building and sustaining military forces consumes vast quantities of resources. The environmental impact of wars begins long before they do.
