Having won re-election, President George W. Bush has a historic opportunity to continue the sweeping changes his Administration had begun in the Pentagon. The new Administration should continue to transform the military by developing the right set of skills and capabilities to meet the security threats of the 21st century, while retaining robust force levels and adequate funding for the military.

Maintaining Robust Defense Budgets. Although defense spending has increased ever since the Clinton Administration, chronic underfunding continues to burden all of the armed services. Even the most recent budget request contained shortfalls, including inadequate funding for such important programs as vehicle armor, military construction, aircraft survivability equipment, and ballistic missile submarine communications. Sustained long-term budget increases are necessary to ensure that America's forces are prepared for an unpredictable future.

The United States could reasonably afford to dedicate up to 4 percent of gross domestic product (GDP) to defense--a level of spending that would be well within historical norms. With the exception of 1948, the United States spent more than 4 percent of GDP on national security in every year from 1941 to 1995. Given a focused and well-balanced modernization strategy, this level of spending would be adequate to maintain a force capable of protecting U.S. territory and interests today, as well as to field an adequate force in the future.

Ballistic Missile Defense. The Bush Administration is on the cusp of declaring operational a ballistic missile defense that can defend U.S. territory against limited ballistic missile strikes. The Administration's first priority should be to bring this operational capability online as soon as possible. Next, the Administration should move to expand and improve this limited defense, using its spiral development process to achieve a more robust global missile defense capability. The most important steps for building on this initial missile defense capability are: (1) aggressively pursuing options to deploy missile defense sensors and interceptors in space, (2) continuing to build the global command and control structure for managing missile defense assets, and (3) expanding missile defense cooperation with friends and allies around the world. Additional steps should include pursuing sea-based deployments of missile defense interceptors, expanding the number of interceptor and sensor sites, continuing to improve the existing Patriot missile defense system, and proceeding with development of the Terminal High Altitude Area Defense system.

Post-Conflict Operations. As demonstrated in Iraq, the United States needs to prepare better for the rigors of post-conflict operations in the 21st century. To this end the United States must define the responsibilities of its armed forces in these operations as well as determine the legitimate roles for other agencies of the U.S. government, host nations, and international organizations. Once defined, the U.S. armed force should be structured to fulfill its mission without subjecting itself to unnecessary strain. During this process it will be necessary to distinguish between post-conflict operations and other operations other than war (OOTW), such as peacekeeping, peacemaking, and humanitarian missions. Although these OOTW missions may share some characteristics, they are not interchangeable.

Over the next four years the Administration should be very careful not to repeat the mistakes of previous Administrations. Even if commitments associated with the war on terrorism decrease, the United States should not become militarily involved in the same kind of missions as it took on in the 1990s. Instead, it should continue to rely on the model that was developed during the Australian-led intervention in East Timor and followed again in Liberia. In each of these cases the United States supported the effort with its unique capabilities, but the overall effort was led by regional interests.

The Military's Role in Homeland Security. Although the Pentagon is not the primary federal agent of homeland security, it does have a vital role to play and must dedicate a portion of its resources to that mission. Two aspects of that mission require particular attention. The National Guard must increase its capacity to respond to catastrophic threats and protection of critical infrastructure. Creating force structures, doctrine, and acquisition programs that could support both domestic security missions and overseas post-conflict and theater-support missions might best accomplish this. The military must also increase its capacity to support maritime security. This might be done by restructuring the Littoral Combat Ship program to support both theater missions and homeland security missions with the Coast Guard.

Transforming the Basing Infrastructure. The U.S. global (domestic and foreign) basing infrastructure must be recalibrated to reflect America's changing and unpredictable national security requirements. President Bush has undertaken two initiatives that will achieve this critical goal--initiating another round of Base Realignment and Closure at home and reconfiguring America's basing infrastructure abroad. This basing transformation is necessary because the current base structure was developed to defend against a largely static and predictable enemy--the former Soviet Union. Today's threats, in stark contrast to those of the Cold War, are dynamic and unpredictable, and therefore demand a flexibility that is currently lacking. A flexible basing structure will promote adaptability in a world of diverse political, strategic, and diplomatic interests. America's commitment to regional stability can no longer be measured by manpower alone. More efficient global basing infrastructure will free up manpower resources and help to alleviate personnel strains. Eliminating excess basing infrastructure will also free up resources that can be reinvested into the Pentagon's critical transformation initiatives. These efforts should top the Bush Administration's national security agenda for the next four years.

Conclusion. In his second term, President Bush has the opportunity to make generational changes to how the nation approaches national security. Doing so, however, will require making some tough decisions.

Jack Spencer is Senior Policy Analyst for Defense and National Security, James Jay Carafano, Ph.D., is Senior Research Fellow for National Security and Homeland Security, and Baker Spring is F. M. Kirby Research Fellow in National Security Policy in the Kathryn and Shelby Cullom Davis Institute for International Studies at The Heritage Foundation.