They say generals are always fighting the last war, but the command structure in place in today's U.S. military looks to have been put in place for use two wars ago.

We are set up to fight the Cold War, where our enemy was the Soviet Union, the key threats were thermonuclear war and the Soviet Union's attempts to establish satellites all over the world, and the weapons of choice were long-range missiles situated in proxy countries.

Today, U.S. enemies are shadowy, their aims are more local than global, their methods are starkly different, and the featured weapon of their biggest strike against our homeland was the humble box-cutter. In short, the present system, the Unified Command Plan, has not kept up.

The structure of five regional commands - CENTCOM (the Middle East), EUCOM (Europe), PACOM (the Pacific Rim), SOUTHCOM (Central and South America) and the new NORTHCOM (North America) - provide more or less even coverage to the entire world, a sound strategy when we were opposed by a global superpower such as the Soviet Union.

But today, the hot spots are more localized and easily identifiable, and our energies and resources should be directed disproportionately to them.

Also, the current Unified Command Plan, like all others before it, focuses strictly on combat operations so the military can avoid being dragged into non-military operations. But today, the Pentagon needs the capacity to integrate with other departments and non-governmental organizations to better manage post-combat operations and other needs.

It is time the Unified Command Plan is replaced with an organizational structure that emphasizes interagency cooperation on the one hand and effective joint combat action on the other.

A new structure, which could be called the U.S. Engagement Plan (U.S.-Plan), would reduce the number of regional military commands to three: EUCOM and PACOM would be replaced by a U.S.-NATO command and a U.S. Northeast Asia operation, and NORTHCOM would remain the military command responsible for the defense of the United States.

In addition, three Joint Interagency Groups, or InterGroups, would be formed: one in Latin America to focus on drug, human and arms trafficking, counterterrorism, civil-military relations and trade liberalization; an Africa-Middle East group to focus on counterterrorism, weapon proliferation, economic development, peacekeeping and transnational crime, and fighting AIDS and other infectious diseases; and one in Central and South Asia to focus on counter-terrorism, weapon proliferation, training of police forces, anti-piracy measures, civil-military relations, crime and AIDS.

These groups, already in limited use in counternarcotics operations in Latin America, the Caribbean and off the Pacific coast of the United States, incorporate resources from multiple agencies under a single command structure for specific missions. Each InterGroup would include a military staff to plan military engagements, war-fighting and post-conflict operations.

When military operations are required, the military staff would be detached from its group to become the nucleus of a standing joint task force. Using this model, the operations in Iraq and Afghanistan would have been commanded by such a joint task force.

Developing the commanders, people, organizations, education and doctrine needed to support this plan will take time and resources. It also would require legislation, modeled on the Goldwater-Nichols Act that established the present system, to outline the requirements, legal authorities and resources.

But the time to begin is now. To prosecute the global war on terrorism, the United States will need unprecedented integration of its military, intelligence, law enforcement, diplomatic and other national security assets. It needs a command structure designed for the challenges of the future, not problems of the past.

And it needs leadership from Congress, which should begin to hold hearings as soon as possible to establish what U.S. strategies for engaging the world will look like in the 21st century and beyond.

James Jay Carafano is a 25-year veteran of the U.S. Army and a senior research fellow in defense and homeland security at The Heritage Foundation.