Balad Air Base, Iraq The concrete goes on forever, vanishing into the noonday glare, 2 million cubic feet of it, a mile-long slab that's now the home of up to 120 U.S. helicopters, a "heli-park" as good as any back in the States.
At another giant base, al-Asad in Iraq's western desert, the 17,000 troops and workers come and go in a kind of bustling American town, with a Burger King, Pizza Hut and a car dealership, stop signs, traffic regulations and young bikers clogging the roads.
At a third hub down south, Tallil, they're planning a new mess hall, one that will seat 6,000 hungry airmen and soldiers for chow.
Are the Americans here to stay? Air Force mechanic Josh Remy is sure of it as he looks around Balad.
"I think we'll be here forever," the 19-year-old airman from Wilkes-Barre, Pa., told a visitor to his base.
The Iraqi people suspect the same. Strong majorities tell pollsters they'd like to see a timetable for U.S. troops to leave, but believe Washington plans to keep military bases in their country.
The question of America's future in Iraq looms larger as the U.S. military enters the fourth year of its war here, waged first to oust President Saddam Hussein, and now to crush an Iraqi insurgency.
Ibrahim al-Jaafari, interim prime minister, has said he opposes permanent foreign bases. A wide range of American opinion is against them as well. Such bases would be a "stupid" provocation, says Gen. Anthony Zinni, former U.S. Mideast commander and a critic of the original U.S. invasion.
But events, in explosive situations like Iraq's, can turn "no" into "maybe" and even "yes."
The Shiite Muslims, ascendant in Baghdad, might decide they need long-term U.S. protection against insurgent Sunni Muslims. Washington might take the political risks to gain a strategic edge - in its confrontation with next-door Iran, for example.
The U.S. ambassador to Iraq, Zalmay Khalilzad, and other U.S. officials disavow any desire for permanent bases. But long-term access, as at other U.S. bases abroad, is different from "permanent," and the official U.S. position is carefully worded.
Lt. Cmdr. Joe Carpenter, a Pentagon spokesman on international security, told The Associated Press it would be "inappropriate" to discuss future basing until a new Iraqi government is in place, expected in the coming weeks.
Right now what is heard is the pouring of concrete.
In 2005-06, Washington has authorized or proposed almost $1 billion for U.S. military construction in Iraq, as American forces consolidate at Balad, known as Anaconda, and a handful of other installations, big bases under the old regime.
They have already pulled out of 34 of the 110 bases they were holding last March, said Maj. Lee English of the U.S. command's Base Working Group, planning the consolidation.
"The coalition forces are moving outside the cities while continuing to provide security support to the Iraqi security forces," English said.
The move away from cities, perhaps eventually accompanied by U.S. force reductions, will lower the profile of U.S. troops, frequent targets of roadside bombs on city streets. Officers at Al-Asad Air Base, 10 desert miles from the nearest town, say it hasn't been hit by insurgent mortar or rocket fire since October.
Al-Asad will become even more isolated. The proposed 2006 supplemental budget for Iraq operations would provide $7.4 million to extend the no-man's-land and build new security fencing around the base, which at 19 square miles is so large that many assigned there take the Yellow or Blue bus routes to get around the base, or buy bicycles at a PX jammed with customers.
The latest budget also allots $39 million for new airfield lighting, air traffic control systems and upgrades allowing al-Asad to plug into the Iraqi electricity grid - a typical sign of a long-term base.
At Tallil, besides the new $14 million dining facility, Ali Air Base is to get, for $22 million, a double perimeter security fence with high-tech gate controls, guard towers and a moat - in military parlance, a "vehicle entrapment ditch with berm."
Here at Balad, the former Iraqi air force academy 40 miles north of Baghdad, the two 12,000-foot runways have become the logistics hub for all U.S. military operations in Iraq, and major upgrades began last year.
The chief Air Force engineer here, Lt. Col. Scott Hoover, is also overseeing two crucial projects to add to Balad's longevity: equipping the two runways with new permanent lighting, and replacing a weak 3,500-foot section of one runway.
Once that's fixed, "we're good for as long as we need to run it," Hoover said. Ten years? he was asked. "I'd say so."
Home away from home
Away from the flight lines, among traffic jams and freshly planted palms, life improves on 14-square-mile Balad for its estimated 25,000 personnel, including several thousand American and other civilians.
They've inherited an Olympic-sized pool and a chandeliered cinema from the Iraqis. They can order their favorite Baskin-Robbins flavor at ice cream counters in five dining halls, and cut-rate Fords, Chevys or Harley-Davidsons, for delivery at home, at a PX-run "dealership." On one recent evening, not far from a big 24-hour gym, airmen hustled up and down two full-length, lighted outdoor basketball courts as F-16 fighters thundered home overhead.
"Balad's a fantastic base," Brig. Gen. Frank Gorenc, the Air Force's tactical commander in Iraq, said in an interview at his headquarters here.
Could it host a long-term U.S. presence?
"Eventually it could," said Gorenc, commander of the 332nd Air Expeditionary Wing. "But there's no commitment to any of the bases we operate, until somebody tells me that."
Army and Air Force engineers, with little notice, have worked to give U.S. commanders solid installations in Iraq, and to give policymakers options. From the start, in 2003, the first Army engineers rolling into Balad took the long view, laying out a 10-year plan envisioning a move from tents to today's living quarters in air-conditioned trailers, to concrete-and-brick barracks by 2008.
In early 2006, no one's confirming such next steps, but a Balad "master plan," details undisclosed, is nearing completion, a possible model for al-Asad, Tallil and a fourth major base, al-Qayyarah in Iraq's north.