Three basic comparisons can be made between weapon system development and energy system development in the US--driving factors, system lifetime, and development time. Weapon system development and response is determined by a perceived threat to national security. Because the threat can change radically in this high technology atmosphere, weapon systems are usually designed for a 5 to 20 year lifetime. Development time from idea to capability is about 20 years on the average. In contrast, energy system development has been influenced by economics--demand, supply, return on investment--until the recent threat created by our dependence on oil. Energy systems are expected to operate 20 to 50 years and even longer. Development time is correspondingly long, i.e., 40 years from idea to large-scale use. The US needs to adopt a ''defense-oriented'' approach to protect its threatened energy security. Geothermal energy from hot dry rock is a new concept. The Hot Dry Rock Program is designed to minimize development time and may become a prime example of how a recognized threat to energy security can be answered by combined government/industry effort.