America’s goals are to promote peace, sustain freedom, and encourage prosperity. U.S. leadership is premised on sustaining an international system that is respectful of the rule of law. America’s political, diplomatic, and economic leadership contributes directly to global peace, freedom, and prosperity. U.S. military strength is essential to achieving these goals, as it assures friends and allies of an unwavering U.S. commitment to common interests.

America’s security role in the world is unique. It provides the basis for a network of alliances and friendships. It provides a general sense of stability and confidence, which is crucial to the growing prosperity that benefits much of the world. And it warns those who would threaten the nation’s welfare or the welfare of U.S. allies and friends that their efforts at coercion or aggression will not succeed.

Yet, as the events of September 11 have made clear, there are many threats against our country and our people, and they take many forms. They range from the threat of major war to the faceless threat of terror. America’s approach to security is to defend our way of life, our people and territory, assist allies and friends in their defense and help create the conditions for international stability and confidence.

The purpose of the U.S. Armed Forces is to protect and advance U.S. national interests and, if deterrence fails, to defeat threats to those interests. The United States has interests, responsibilities, and commitments that span the world. As a global power with an open society, the United States is affected by trends, events, and influences that originate from beyond its borders.

Ensuring U.S. security and freedom of action is a paramount interest, and includes protecting U.S. sovereignty, territorial integrity, and freedom; the safety of U.S. citizens at home and abroad; and critical U.S. infrastructure.

The U.S. must also honor and uphold its international commitments. This involves protecting the security and well being of allies and friends; preventing hostile domination of critical areas, particularly Europe, Northeast Asia, the Asian littoral, and the Middle East and Southwest Asia; and promoting prosperity in the Western Hemisphere.

The U.S. also has an interest in the vitality and productivity of the global economy; the security of international sea, air, and space, and information lines of communication; and access to key markets and strategic resources.

Protecting these interests requires commitment and support. It includes effective diplomacy, a strong economy, and a watchful and ready defense. When U.S. interests are protected, America and its friends prosper from peace and freedom. When U.S. interests are challenged, the nation must possess the strength and resolve to defend them.

The American people were relieved when the Cold War ended a decade ago. They looked around and did not see an adversary whose stated intent was to destroy the United States. They saw the growth of market economics and governments based on representative democracy taking root around the globe. They saw a powerful U.S. economic expansion creating unprecedented prosperity. There was a temptation to believe that this favorable circumstance was a permanent condition.

The events of September 11 presented a different view of the world: The 21^st century security environment is different from that we faced in the 20^th century in important ways it is more complex and dangerous.

Well before the events of September, senior Defense Department officials, through the vehicle of the Quadrennial Defense Review, determined that contending with uncertainty must be a central tenet in U.S. defense planning. Too much of the Department’s planning over the decade of the 1990s had focused on a few familiar dangers rather than the broad array of potential challenges of consequence to U.S. interests and the nation’s inherent vulnerability to asymmetric attacks. They concluded that U.S. defense planning must assume that surprise is the norm, rather than the exception. Adapting to surprise adapting quickly and decisively must be a hallmark of 21^st century defense planning.

The Department’s senior leadership identified features and trends of the security environment that define today’s geopolitical and military-technical challenges, and which highlight critical operational challenges that the nation’s armed forces will need to master in the future.

Although U.S. military forces enjoy advantages in many aspects of armed conflict, the U.S. will be challenged by adversaries that possess or seek capabilities and design novel concepts to overcome those advantages. The United States cannot predict with a high degree of confidence the identity of the countries or the actors that may threaten its interests and security. But it is possible to identify the trends that will provide adversaries with capabilities and opportunities to do harm to the U.S.

Diminishing protection afforded by geographic distance. As the events of September 11 have demonstrated, the geographic position of the United States will not provide immunity from direct attack on its people, territory, or infrastructure. Enemies are finding new ways to overcome the difficulties of geographic distance. It is clear that over time an increasing number of states have and will acquire cruise and ballistic missiles of steadily increasing range. Moreover, economic globalization and the increase in travel and trade across U.S. borders have created new vulnerabilities and opportunities for hostile states and actors to exploit and to perpetrate attacks on the U.S. homeland.

Regional Security Developments. Regional powers are developing capabilities to threaten stability in regions critical to U.S. interests. In particular, Asia is gradually emerging as a region susceptible to large-scale military competition. Along a broad arc of instability that stretches from the Middle East to Northeast Asia, there exists a volatile mix of rising and declining regional powers. The governments of some of these states are vulnerable to radical or extremist internal political forces or movements. Many of these states field large militaries and already have or possess the potential to develop or acquire weapons of mass destruction. Iraq, Iran, and North Korea are arming with long-range missiles and are seeking or acquiring nuclear, biological, and chemical (NBC) weapons. Analyses of regimes continue to support global terrorist organizations and to terrorize their own people.

Asia. Maintaining a stable balance in Asia will be both a critical and formidable task. The possibility exists that a military competitor with a substantial resource base will emerge in the region. The Asian littoral represents a particularly challenging area for operations. The distances are vast and the density of U.S. basing and en route infrastructure is lower than in other critical regions. This places a premium on securing additional access and infrastructure agreements and on developing systems capable of sustained operations at long distances with minimal theater-based support.

Middle East. The U.S. and its allies and friends will continue to depend on the energy resources of the Middle East, a region in which several states pose conventional military challenges and seek to acquire NBC weapons. Iran aggressively pursues these weapons. Iraq has worked to develop anthrax, nerve gas, and nuclear weapons for over a decade. Both states are also developing ballistic missile capabilities and expanding their military means to coerce states friendly to the U.S. and to deny U.S. military forces access to the region.

Europe. With the notable exception of the Balkans, which though not at war remains unstable, Europe is largely at peace. Central European states are becoming increasingly integrated with the West, both politically and economically. An opportunity for cooperation exists with Russia. It does not pose a large-scale conventional military threat to NATO. It shares some important security concerns with the United States, including the problem of vulnerability to attack by ballistic missiles from regional aggressors, the danger of accidental or unauthorized launches of strategic weapons, and the threat of international terrorism. Yet, at the same time, Russia pursues a number of policy objectives contrary to U.S. interests, both overt and covert.

Western Hemisphere. While the Western Hemisphere remains largely at peace, the danger exists that crises or insurgencies might spread across borders, destabilize neighboring states, and place U.S. economic and political interests at risk. U.S. homeland security cannot be divorced from that of its neighbors.

Increasing challenges and threats emanating from the territories of weak states and ungoverned areas. The absence of capable or responsible governments in many countries in wide areas of Asia, Africa, and the Western Hemisphere creates a fertile ground for non-state actors to engage in terrorism, acquisition of NBC weapons, illegal drug trafficking, and other illicit activities across state borders. A terrorist underworld including such groups as al Qaeda, Hamas, Hezbollah, Islamic Jihad, and Jaish-I-Mohammed operates in such areas. In an era of catastrophic terrorism, the United States cannot afford to ignore the anarchy that threatens a number of regions of the world.

In several regions, the inability of some states to govern their societies, safeguard their military armaments, and prevent their territories from serving as sanctuary to terrorists and criminal organizations poses a threat to stability and places demands on U.S. forces. Afghanistan is but one example of the security implications for the U.S. of such weak or ungoverned areas. Conditions in some states, including some with nuclear weapons, demonstrate that threats can grow out of the weakness of governments as much as out of their strength.

Diffusion of power and military capabilities to non-state actors. September 11^th demonstrates that terrorist groups possess both the motivation and capabilities to conduct devastating attacks on U.S. territory, citizens, and infrastructure. Often these groups have the support of state sponsors or enjoy sanctuary and protection of states, but some have the resources and capabilities to operate without state sponsorship. Terrorist networks and their supporters are exploiting globalization and actively seek NBC technology. There can be little doubt that terrorist organizations like al Qaeda that possessed such weapons would attempt to use them.

Increasing diversity in the sources and unpredictability of the locations of conflict. Together, these trends produce a geopolitical setting that is increasingly complex and unpredictable. Unlike the recent past, the U.S. will not be able to develop its military forces and plans primarily to confront a specific adversary in a specific geographic area. The United States could face the need to intervene in unexpected crises against opponents with a wide range of capabilities. Moreover, these interventions may take place in distant regions where urban environments, other complex terrain, and varied climatic conditions present major operational challenges.

Technology in the military sphere is developing as rapidly as the changes reshaping the civilian sector. The combination of scientific advancement and globalization of commerce and communications have contributed to several trends that significantly affect U.S. defense strategy and planning:

Rapid advancement of military technologies. The ongoing revolution in military affairs is changing the conduct of military operations. Technologies for sensors, information processing, precision guidance, and many other areas continue to advance at a rapid pace. On the one hand, states hostile to the U.S. are significantly enhancing their capabilities by integrating widely available off-the-shelf technologies into weapon systems and armed forces. On the other hand, the revolution in military affairs holds the potential to confer on the United States the opportunity to sustain and extend its advantages in key areas of military technology, systems, and operational practices. Exploiting the revolution in military affairs requires not only technological innovation but also development of operational concepts, new organizational adaptations, and training and experimentation to transform a country’s military forces.

Increasing proliferation of nuclear, biological, and chemical weapons and ballistic missiles. The proliferation of NBC technology, materiel, and expertise has provided potential adversaries with the means to challenge directly the safety and security of the United States and its allies and friends. The pace and scale of ballistic missile proliferation has exceeded earlier intelligence estimates and suggests this challenge may grow at a faster pace than previously expected. Likewise, the biotechnology revolution and bio-terror portend a future with increasing threats of advanced and more sophisticated forms of attack. Hostile regimes and terrorist organizations will seek to acquire and use NBC weapons and ballistic missiles to attack the vulnerabilities of open societies.

Emergence of new arenas of military competition. Technological advances create the potential for new forms of competition in space and cyberspace. Space and information operations have become the backbone of networked, highly distributed commercial civilian and military capabilities. No nation relies more on space for its national security than the United States. Yet elements of the U.S. space architecture ground stations, launch assets, and satellites in orbit are threatened by capabilities that are increasingly available. This opens up the likelihood that assuring the use of space while denying the use of space to adversaries will become a key objective in future military competition. Similarly, many states are developing offensive information operations to attack and disrupt military and commercial information systems.

Increasing potential for miscalculation and surprise. Together, these military-technical trends create an increased potential for miscalculation and surprise. In recent years, the United States has been surprised by the speed with which other states have progressed in developing weapons of mass destruction and ballistic missiles. In the future, it is unlikely that the United States will be able to predict accurately how successfully other states will exploit the revolution in military affairs, how rapidly potential or actual adversaries will acquire NBC weapons and ballistic missiles, or how competitions in space and cyberspace will develop.