High Performance Computing (HPC) is a key, enabling technology that is essential to assure that U.S. Forces maintain dominance on the battlefield with minimal risk to life, even against numerically superior forces. Tracing requirements from the President's National Security Strategy to our National Military Strategy as defined by the Military Services, Joint Chiefs of Staff, and the warfighting Commanders in Chief (ClNCs), one common denominator prevails-the need for militarily superior technology. Technology is a key discriminator in our deterrence of conflicts; failing to deter aggression, technology can be the difference between success and failure on the battlefield. HPC enables advanced modeling and simulation concepts and capabilities that can be used to assess the value of individual components or new weapon systems' projected performance levels. Data collected from modeling and simulation will assist milestone decisions by pointing to research, development, test and evaluation (RDT & E) of most value to the warfighter. Through the use of HPC resources for example, it is possible to simulate the capabilities of a new weapon system and to measure that system's impact on existing tactics and the predicted outcome of a military engagement (using tens of thousands of entity types). As a result, senior DoD leadership will have data to assist in the decision-making process as early as possible. These data will provide information about whether to proceed, modify, or cancel a program and where to best invest our RDT & E resources. Other mission-critical areas that could be greatly improved by advanced modeling and simulations using HPC include ocean modeling and weather prediction, bomb damage assessment, water tampering determinations, modeling of radio frequency systems and antenna designs, environmental impacts/ cleanup, and counter-proliferation and counter-terrorism scenarios.