..._The number of American troops in South Korea (news - web sites), now about 37,000, likely will decline. The Americans want a reduction of perhaps one-third, or about 12,000 troops, which would be the biggest cut in decades. It's one that makes the South Korean government nervous.

_The forces that remain will be more "expeditionary." They would be positioned in ways to enable American commanders to send them elsewhere in the Asia-Pacific region. It's a major change, reflecting Defense Secretary Donald H. Rumsfeld's view that the fight against terrorism requires a more flexible approach to use of U.S. troops worldwide.

_Though smaller in number, the U.S. military presence would be more capable in important ways. By moving farther south of the Demilitarized Zone that has separated North and South Korea since the war ended in 1953, the U.S. Army would be able to respond more quickly to an attack by the North. As currently positioned, the Army would have to withdraw south of Seoul first, while in range of the North's long-range artillery, before organizing a counteroffensive.

"No longer will our forces be based near the DMZ as a political `trip wire,'" Paul Wolfowitz, the deputy secretary of defense, told Congress this summer...