The study documents past contributions of supercomputing to national defense and to scientific discovery, together with evidence of its increasing importance in the future. Numerical simulation and digital data analysis have become essential to research in most disciplines, and many disciplines have insatiable needs for more performance. In areas such as climate modeling or plasma physics, there is a broad consensus that up to seven orders of magnitude of performance improvements will be needed to achieve well-defined computational goals; and there is a clear understanding of the likely advances that will accrue from the use of better performing supercomputing platforms. Supercomputers are essential to the missions of government agencies in areas such as intelligence or stockpile stewardship; they are an essential tool to the solution of important societal problems. Finally, technologies developed on supercomputers broadly contribute to our economy. Examples include application codes (such as NASTRAN) that were initially developed in national labs and run on supercomputers and then disseminated to broad industrial bases; as well as core IT technologies (such as multithreading or vector processing) that were pioneered on supercomputers and migrated to broadly used IT platforms. For reasons explained later, we expect this “trickle-down” process to continue, and perhaps intensify, in coming years. Although it is hard to quantify in a precise manner the benefits of supercomputing, the committee believes that the returns on increased investments in supercomputing will greatly exceed the cost of these investments.

The public sector is the leading user and purchaser of supercomputers: According to International Data Corporation (IDC), more than 50 percent of high-performance computer (HPC) purchases and more than 80 percent of capability system purchases in 2003 were made by the public sector. The reason for this is that supercomputers are used mostly to produce "public goods" and are essential for many government missions. They are used to support government funded basic and applied research; and they are used to support DoD or DOE missions, and the missions of intelligence agencies. Supercomputing technologies have often migrated to mainstream computing, but on a time table that is longer than the horizon of commercial computer companies.

This state of affair implies that the government plays a crucial role in the supercomputing industry, since its acquisitions have a major impact on the health, indeed, the existence of such an industry. Historically, the government has played an active role in ensuring that supercomputers are available to fulfill its needs by funding supercomputing R&D and by forging long-term relationships with key providers. While active government intervention has risks, it is necessary in areas where the private market is nonexistent or too small to ensure a steady flow of products and technologies that satisfy government needs. Thus, one clearly needs an active government policy to ensure a steady supply of military submarines or aircrafts; whereas no active government involvement is needed to ensure a steady supply of PCs. Are supercomputers more like military submarines or like PCs? To answer this question we need first to look at the current state of supercomputing in the US.