Sky marshals, metal detectors and multiple identification checks may increase security in the corporeal world, but guarding the nation's information superhighway requires different tactics. And in the information age, homeland security must extend into the digital realm, or even a tiny crack could allow adversaries into some of the most important systems in the world today.

The battlespace network trialed in the woods of Kentucky and grown from the sands of Kuwait provided the necessary connectivity for the U.S. Army's 101st Airborne Division (Air Assault) to strike deep into Iraq. Not all of the assets assembled and deployed by the division's 501st Signal Battalion were exploited to their fullest, and some proved more important than originally envisioned. Yet, the network linked the air assault division as its location and mission changed with the flow of battle.

The deep thrust into Iraq by the U.S. Army's 101st Airborne Division in operation Iraqi Freedom was enabled as much by kilobytes as by helicopters. An advanced command, control and communications architecture allowed the geographically dispersed mobile forces to remain in contact with their individual commanders as well as with the division headquarters.

Last year, I discussed in my commentary how information must be available-as freely as oxygen in the air-to virtually everyone. In presenting this point of view, I offered that power lies in how one uses information.

The newest U.S. combatant command, tasked with defending the homeland, is taking a military approach to using civilian assets. This does not involve discarding existing U.S. laws that mandate separation of military activity from local responsibilities. Rather, it involves organizing and coordinating threat protection and emergency response efforts to maximize available federal, state and local government resources. And, it may include placing the military command under civilian leadership.

The newly independent U.S. Air Force Space Command is focusing on integrating exo-atmospheric operations with lower altitude activities, including ground campaigns. These operations in space, which range from communications to precision guiding of munitions, are becoming less of a separate warfighting aspect and more of a united element of high-technology network-centric warfare.

While military combatants continue to fight the war against terrorism on the battlefield, U.S. government officials are stepping up work to protect the borders of cyberspace. Information infrastructure security is such a high priority that government agencies are now required to provide reports on risk assessments, system security needs and security plans before they receive program funding.

The newest U.S. government plan for cybersecurity proposes some short-term remedies while acknowledging that long-term security goals may take years to come to fruition. First published in draft form last fall, the new version establishes a list of priority programs but eschews detailed directives. This changes the thrust of the strategy from an operations manual to a list of guidelines.

The U.S. Air Force is embracing force transformation at the operational and organizational levels and moving away from platform-based modernization. To meet its requirements, the service is selecting new technologies and equipment based on the ability to enhance a variety of capabilities instead of a few narrowly defined missions.

More than 10 years after the end of the Cold War, the U.S. Defense Department is shedding old constructs from that period that have been hindering the department's new thrust into space. A major component of these changes places the primary responsibility for acquiring and launching military space systems in the hands of the U.S. Air Force. Within the service, new commands and offices also are being established to interface with homeland security efforts and joint organizations such as the U.S. Northern Command.