President George W. Bush, Defense Secretary Donald Rumsfeld, and General Tommy Franks deserve applause for their leadership and steadfastness in the prosecution of the war on terrorism. The innovative methods used in this conflict have transformed the way we will conduct future conflicts.

Leading the way in military innovation and transformation has been our use of space. Central Command's General Franks, in his Feb. 7 statement before the Senate Armed Services Committee, stated that the use of unmanned aerial vehicles, precision-guided munitions, and command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR) systems proved to be "very effective" in the prosecution of what he considered to be "the most accurate war in the history of the United States."

Underpinning the use of these modern tools of war is dependency on space assets, such as the Global Positioning System (GPS) and our satellite communications networks. Our nation's warfighters rely more and more on space systems. In fact, General (now Secretary of State) Colin Powell, while chairman of the Joint Chiefs of Staff, said the United States learned from Operation Desert Storm that it had "to achieve total control of space if [our nation is] to succeed on the modern battlefield."

Our nation's growing dependence on space is not limited to military purposes. Our economy is becoming increasingly dependent on space. We use satellite communications for everyday things like pagers, cell phone networks, pay-at-the-pump gas service, and satellite television. Backpackers, hunters, fishermen and lost tourists use GPS to find their way.

Without question, space has become America's major "center of gravity," and our enemies know it. It is only a matter of time before an adversary figures out how to deny us use of these systems. A nuclear antisatellite (ASAT) weapon can indiscriminately destroy many satellites in a single blast, while conventional ASATs and microsats (very small satellites) can be far more surgical in their attacks.

Our ability to defend against attacks on our space systems is limited at best, and more focus to bolster our space defenses is desperately needed. According to General Ralph Eberhart, commander of U.S. Space Command, space control - the ability to protect one's own space assets while denying an adversary's use of in-orbit resources - is "still at idle." Lieutenant General Chuck Wald, one of the directors of the air campaign in the Afghan conflict, said recently that the space-enabled advantage the United States enjoys in precision strike would undoubtedly be the focus of attack from future adversaries. I agree. It is critical for the United States to pay serious attention to space systems defense. We need to devote more resources to strengthening the advantage space systems lend us over potential adversaries and to protect our space systems from attack as we press ahead with our utilization of space as part of our overarching strategic vision.

Our adversaries of the future will target our reliance on space assets. In July 2000, the Xinhua news agency reported that China's military is developing methods and strategies for defeating the United States military in a high-tech and space-based future war, arguing, "For countries that could never win a war by using the method of tanks and planes, attacking the United States space system may be an irresistible and most tempting choice."

Attacks can come from a number of sources, to include the aforementioned ASATs, jamming, electromagnetic pulse attack and directed-energy weapons. The Chinese press has noted their government's development of parasitic satellites that attach to a functioning host satellite with the ability to degrade or disrupt service. It is imperative that we aggressively pursue options to protect ourselves from attack - both offensive systems such as kinetic energy ASAT and space-based laser (SBL) and defensive systems such as hardened facilities and increased surveillance.

A recent national intelligence estimate stated that the United States most likely would be faced with the threat of intercontinental ballistic missile (ICBM) attack on its homeland from adversaries before 2015. Any nation that can launch ICBMs at us can directly threaten our systems in space. However, I believe our space systems will see other threats far sooner than that. It is past time to start investing in defenses against both these threats, and opposition to space "weaponization" cannot deter us.

Space has been weaponized for years, with military operations relying on satellite communications and precise GPS navigation. Let us not forget that ICBMs we've had deployed since the 1960s travel through space to reach their intended targets.

One of the best ways to defend against both ballistic missile attack on our homeland and ASAT attack on our space systems is to develop a boost-phase ballistic missile interceptor. The U.S. Air Force had undertaken a significant first step along this path with the SBL Integrated Flight Experiment (IFX) program, which was to be a space-based proof-of-concept demonstration of a directed-energy weapon against a boosting ballistic missile target.

Conducting the demonstration would have yielded important information on a future operational system. Unfortunately, SBL IFX funding was slashed to roughly $50 million per year, effectively killing the program and threatening its technology base. There is no other program on the books that can meet the timelines to combat a boosting strategic missile anywhere on the globe. This shortfall must be redressed.

In addition, the nation absolutely must develop the other needed components of the missile defense system, such as the Space Based Infrared System - Low (SBIRS-Low) for surveillance, as soon as possible. Another area that lacks focus is the establishment of an overarching strategic view of space. The Space Commission, which was created by my legislation and chaired by Donald Rumsfeld before he was selected as Secretary of Defense, understood the critical importance of space to our nation. The commission's report stated, "The United States has a vital national interest in space. Space should be high among the nation's security priorities. It deserves the attention of the national leadership, from the president down."

I am concerned that we have not yet embraced this notion. The commission's top two recommendations, establishment of space as a national security priority and establishment of a Presidential Space Advisory Group, have not been implemented, and the third recommendation, the establishment of a Senior Interagency Group for Space, fizzled after just a few meetings.

I met recently with Peter Teets, who has dual roles as the under secretary of the Air Force and the director of the National Reconnaissance Office (NRO). I was very impressed with his plans to ensure the defense and intelligence space organizations capitalize on their synergies and best practices. Teets is the right person for the job at an important time. However, I am concerned he will only be able to do so much from his position without leadership from the top.

Although "dual-hatting" the position and broadening scope of authority and responsibility (e.g., making Teets the Department of Defense space milestone decision authority) is a step in the right direction, only the organizations under his direct control, the Air Force and NRO, will be required to follow his direction. What is needed is leadership within the National Security Council to chart our course in space over the next 20 years and break down interagency barriers to achieving those goals.

Issues like the development of space-plane capabilities, improvement of our GPS capabilities, and overall use of the radio frequency spectrum cannot be resolved by the Defense Department alone. We must follow up to ensure needed funding is available to achieve our vision. In his position, Teets can only affect this so much, without control over the larger national space community.

It shouldn't take another catastrophic event like Sept. 11 to awaken the United States into action. The war on terrorism has rightly consumed the full attention of the national leadership, and we must continue to provide sufficient funding to prosecute the war and protect our troops in combat. We also must act vigilantly and prepare now for any future threats. Robust missile and space defenses are essential for protecting lives, ensuring freedom from terrorism, and safeguarding the economy.

Sen. Bob Smith (R-NH) is the former chairman of the Senate Armed Services Committee Subcommittee on Strategic Forces. He is the author of the legislation that created the Space Commission.