In today's interconnected battlefield, our war fighters are increasingly reliant on capabilities at domestic military installations to support critical missions, often in near real time. Many of the domestic installations of the U.S. Department of Defense (DoD) also support everything from sensitive research and development facilities such as microelectronics and biological laboratories to large industrial plants such as shipyards and aviation depots. These facilities depend on the electricity provided by the commercial electric grid. Extended-duration outages on the domestic electric grid will therefore both significantly affect the operational mission of the DoD and bring substantial economic consequences. The changing nature of electricity markets presents new opportunities for the DoD to reduce electricity costs while addressing its energy security needs. Demand response, ancillary service markets, and real-time pricing offer large consumers of electricity such as military installations a significant opportunity to use installation assets during grid-tied operation. Nevertheless, this is an opportunity the DoD can only exploit if it does so in a secure fashion, well protected from cyber threats.