Oil is a commodity of basic strategic importance. No modern defence system can be maintained and no wars fought without a great supply of oil. Thus, significant quantities of scarce oil resources are currently being diverted for military purposes, resulting in less constructive uses of natural energy resources for humanitarian purposes.
Oil is not renewable. It is a limited resource becoming scarcer, as are other natural energy resources. These resources could be used to develop and maintain higher standards of living throughout the world, but the achievement of a high-quality civilization is impeded by the use of these resources for aggressive purposes.
The current high standards of living (which include freedom) in the developed countries can only be assured of continuation if there is a substantial defence network in these countries.