The plan has shifted toward a more mobile force:

The Brookings Institution recently conducted a "war game" to test how a U.S.-led invasion of Iraq might unfold, assuming the use of 300,000 U.S. troops - and found that even with that many troops, their hands would be full.

Those troops would be needed not merely to conduct the invasion and topple Hussein, but to contain the threat of a weapons of mass destruction attack on Iraq's neighbors, intervene in fighting that might occur between Turkey and the Kurdish minority in northern Iraq and begin the process of restoring order in Iraq after Hussein falls, said Kenneth Pollack, a former member of President Bill Clinton's National Security Council.