Top U.S. Defense officials say President Bush's plan to reposition American military power overseas is intended to put U.S. forces in a better position to respond to potential conflicts and the threat posed by terrorism. To do that, tens of thousands of American troops will be brought home from Europe while hundreds of U.S. military facilities overseas will be closed as part of what defense experts describe as the largest U.S. military realignment since the end of the Cold War.

There are more than 230,000 American troops assigned to bases overseas, with the most in Germany, Japan and South Korea. Now, more than a decade after the end of the Cold War, the Pentagon plans to bring home as many a 70,000 of them, along with as many as 100,000 family members and civilian employees.

The goal is to improve the U.S. military's ability to respond to the new challenges posed by terrorism and regional conflicts and move beyond what has been largely a Cold War posture, one designed to contain the threat once posed by the Soviet Union.

"They've tried to find posturing the forces in a way that they can be more nimble and more quickly respond to key areas that would be potential hot spots around the world," says John Robinson, the managing editor of Defense Daily. "A lot of these things are really academic and long overdue. For example, why in the world is the United States Navy based in London? This isn't World War two anymore. It doesn't make any sense in the world to have a major headquarters in London. That should be moved somewhere closer to the Mediterranean, like Naples where it's being sent."

Germany is one area where the Pentagon intends to replace thousands of troops comprising two army divisions with a much smaller brigade, one less reliant on outdated equipment and capable of responding to conflicts in Europe and beyond more rapidly.

Defense Secretary Donald Rumsfeld has long argued that capabilities are more important than numbers, meaning that in future conflicts, rapid reaction forces equipped with 21st century technology will be more important than the actual number of troops deployed.

"The Rumsfeld doctrine is to have relations with a lot of these host countries, bring your forces, stay there for 30, 60 days, do an exercise, or some sort of urgent mission, and then come back," says John Robinson of Defense Daily.

Defense analysts say another issue affecting Pentagon deployment decisions are restrictions placed by host governments on movements and activities of American forces. Speaking to reporters about the military realignment during his flight back from Russia, Secretary Rumsfeld said: "We want our forces where they are wanted. We want our forces where we have the right kinds of legal arrangements and SOFA's, status of forces agreements and the like."

The first troops from Germany are not expected to be brought home before late next year at the earliest and the entire military realignment could take more than a decade to carry out. Noting there are more than 5,000 U.S. military facilities overseas, one senior defense official says many of them are a legacy of the Cold War and no longer needed.

The Bush administration has been in intensive consultation with U.S. allies about its troop realignment plans. While there was no immediate official reaction to the proposal, there were expressions of concern from local German leaders about the effect a reduction in U.S. troops would have on the economy.