Matching an effort to modernize the U.S. military at all levels, the Pentagon and its NATO partners have begun reviewing the best locations for U.S. military bases abroad and the ideal force posture for U.S. troops overseas.

With the Cold War over and few, if any, military threats in Europe, the United States may pull military bases out of old North Atlantic Treaty Organization (search) countries such as Germany and move them to more friendly countries like Romania and Bulgaria.

Military planners say that operations in Kosovo, Afghanistan and Iraq have demonstrated that heavier military operations aren't necessarily better and that smaller, more agile units can do the job just as well and often in less time.

"The larger question really is what is the appropriate posture for the U.S. Armed Forces in terms of basing," said Tom Szayna, senior political scientist at RAND Corp. "They can react in a robust and quick fashion to any crisis happening anywhere in the world, really."

Although Defense Secretary Donald Rumsfeld (search) hasn't been very forthcoming with details on the process, he said Thursday that the U.S. military's presence will be adjusted to "fit the 21st century."

"It seems to me that so many things have changed in the world since those forces were put there [during the Cold War era], they're now spread out through dozens and dozens of places throughout the world," he said. "That's not efficient."

About 250,000 U.S. military men and women are stationed abroad. Of them, 118,000 are in Europe, including 71,000 in Germany. The Asia-Pacific region houses 90,000 U.S. personnel, with just under 40,000 of them in Japan and another 37,000 in South Korea.

"The ultimate test is, how capable, how lethal, how effective is what you have? It does not necessarily go to the total number of forces," Rumsfeld said.

The decision to relocate also coincides with recent reluctance or outright hostility toward the United States.

The U.S. military shut down its last major military mission in Turkey on May 1. Now that Saddam Hussein is gone, no-fly zone patrols of northern Iraq originating out of Turkey (search) are no longer necessary. Aside from that, the Turkish government also wouldn't let the United States use its bases to launch Operation Iraqi Freedom. 

By summer's end, U.S. troops will pull out of bases in Saudi Arabia (search), where their presence has been a source of anti-American sentiment. Saudi bases were used to mount flights over a no-fly zone in southern Iraq.

The Pentagon is looking at changing the makeup of U.S. forces in South Korea and Central Asia as well.

"Given a changed security environment and the fact that we wish to use our forces to the fullest, we do not wish to have forces in areas where there is a groundswell of opposition to our presence," Szayna said.

The force size may be boosted in areas of current concern, such as Asia and in the Middle East, where terrorism concerns are mounting.

American Enterprise Institute defense expert Tom Donnelly said various countries' diplomatic approach to the Iraq war may speed up the relocation process. For instance, France and Germany, among other nations, tried to block action against Iraq.

"If nothing else, the diplomatic shakeout in the Iraq crisis is going to get that process going, is going to shape it, and is going to accelerate it," Donnelly said. "We'll no longer be able to really pretend that NATO as we're used to it is a real go-to-war, shoulder-to-shoulder bunch of allies."

Heritage Foundation defense expert Jack Spencer disagreed.

"I don't think that one's support of war in Iraq or lack thereof will drive our basing ambitions," he said.

NATO Supreme Commander U.S. Gen. James Jones (search) is reviewing moving European bases eastward. Jones, who is also the head of U.S. forces in Europe, plans to visit all 19 NATO member countries as well as the seven eastern European countries soon to be full members by the end of July. The hope is to have a new basing system in place by March 2004.

Before that happens, though, some in Congress want to make sure they have a say in the process.

Sens. Kay Bailey Hutchison, R-Texas, and Dianne Feinstein, D-Calif., recently introduced a bill that would create a commission to conduct an across-the-board evaluation of overseas military bases.

"America faces new threats since the Cold War, yet our allocation of military resources abroad has remained static," Hutchison said.

She stressed the need to put bases in countries that don't limit operations. Germany, for one, has limited U.S. ability to fly helicopters at night, to conduct live-fire exercises or to move vehicles during war games.

"Restrictions imposed by host countries can severely limit opportunities for our forces to conduct realistic training," Hutchison said. "For our deployed troops to effectively perform their missions, they need facilities that allow optimum training."