The American withdrawal from Iraq marks the beginning of one of the largest relocations of military hardware and manpower in recent years. But much of the equipment will not be returning to the United States.
Instead, some will remain with the Iraqi security forces and some will be shipped to Afghanistan. But as important, millions of tons of armor and weaponry will be used to restock huge U.S.-run warehouses across the Middle East -- in case it is needed in the future.
The plans follow a pattern set by the military for the U.S. invasion of Iraq in 2003 and again for the troop buildup in 2007, when the Defense Department drew on equipment stored around the Persian Gulf region, including in massive facilities in Kuwait and Qatar.
Equipment removed from Iraq will be sent to those warehouses, officials said, to ensure that the military is able to respond to a variety of contingencies, including possible Iranian aggression or renewed violence in Iraq.
But other countries in the Middle East are watching warily as the U.S. plans unfold. Many foreign officials want to ensure the U.S. drawdown in Iraq does not leave them unprotected. But the U.S. remains unpopular in the region, and citizens in most Arab countries do not want a large U.S. presence on their territory.
Military experts believe that stockpiling weaponry is a good solution, avoiding the provocation posed by having troops on the ground, but giving the U.S. a head start in case military intervention is needed.
"The materiel is not that big a deal," said Andrew M. Exum, a fellow at the Center for a New American Security. "When people in the Middle East think about the American presence, they think about bodies on the ground, not materiel."
Other experts said the United States must reassure its allies that the equipment stored in the area is for defensive purposes.
"What nobody wants to do is see the U.S. posture for an attack on Iran," said Anthony H. Cordesman, a scholar at the Center for Strategic and International Studies. "The rhetoric here is, 'We would love for you to stay, but we don't want to be the springboard for some sort of idiotic exercise in Iran.' "
Just replenishing the warehouses can be sensitive. Seeking to downscale the U.S. presence in its country, the Kuwaiti government has said the military may store only equipment that would be used for the defense of Kuwait.
The Pentagon said it is adhering to those rules, but U.S officials also believe the Kuwaiti position is open to negotiation.
Historically, Kuwaitis have been tolerant of American military activities in their country because of the successful U.S.-led campaign that drove Iraqi troops out of their emirate in 1991. But many there no longer view Iraq as a critical threat.
Military officials declined to say exactly how much equipment would be repositioned in Kuwait or elsewhere. In the past, the military has stored enough equipment for a heavy brigade each in Kuwait, Qatar and South Korea and for three in Europe. The Army and the Marine Corps also maintain stores of equipment on ships.
To avoid expanding the warehouses, U.S. officials must choose carefully what to store.
"You are going to have to make very hard choices about what equipment you leave behind," Cordesman said. "The force mix you put into the gulf is not going to be the one designed to defeat the Iraqi army. But you do face a series of major challenges from Iran."
Gone from the stocks will be most of the soft-skinned Humvees and unarmored trucks. In their place will be the heavily armored Mine Resistant Ambush Protected vehicles, or MRAPs, said Maj. Gen. Kenneth Dowd, the director of logistics for U.S. Central Command, which oversees U.S. forces in the Middle East.
"It will be primarily the big gear, stuff like MRAPs, tanks," Dowd said. "So we don't have to move and lift all this heavy stuff."
Central Command is working on its drawdown plan for Iraq and has run some tabletop exercises, or "rock drills," to test plans to pull out of Iraq.
"We are working six, seven days a week putting this plan together," Dowd said. "We've done a couple of rock drills, laid out all the units, when they would move. . . . It is a good plan."
The pace of the withdrawal of equipment is beginning to increase. The bulk is likely to come out through Kuwait, although the military has also stepped up its use of the Iraqi port of Umm al Qasr. Last year 8,500 containers were shipped out of Umm al Qasr. In the first two months of this year, 3,000 containers have been removed.
Although Central Command is not giving exact timetables or cost figures on the logistics mission, military officials acknowledge the challenge before them.
Retired Army Lt. Gen. William "Gus" Pagonis, who oversaw the logistics effort in the 1991 Persian Gulf War, said it would take a long time to get the equipment out.
"The bottom line is it is going to take a good 18 months to get out, but you can expedite that by dumping it all into Kuwait," Pagonis said. "And a lot of stuff can be left for Iraqi forces."
The military has begun identifying equipment that will be sold or given to the Iraqis. That includes armored Humvees that are needed by the Iraqi military and generators that would be too costly to ship back to the U.S.
"If it doesn't make sense to bring it home, we are looking at opportunities to help the Iraqis stand up their units," Dowd said.
The military is also going through its equipment to determine what stocks should be diverted to Afghanistan, where an increase in the number of U.S. forces will require additional hardware. Equipment chosen for that war will be sent to Kuwait, repaired, then shipped directly to Afghanistan, Defense officials said.