U.S. warplanes are now operating over Baghdad with near impunity as fighters and bombers circle the Iraqi capital to support ground forces and slow-moving Predator reconnaissance drones fly over the city for 12 hours at a time, the commander of U.S. air forces in the Persian Gulf region said yesterday.

Air Force Lt. Gen. T. Michael Moseley, briefing reporters by telephone from his headquarters in Saudi Arabia, said the focus of the air war shifted yesterday from attacking Republican Guard divisions south of Baghdad to providing close air support over the capital on a 24-hour basis.

Heavy airstrikes against Iraqi President Saddam Hussein's palaces and other government facilities in Baghdad, Moseley said, "have begun to wane for all the right reasons -- we have coalition ground forces in the city now."

The new "concept of operations," Moseley said, calls for aircraft to be "stacked" over Baghdad and directed by airborne controllers on either side of the Tigris River working in concert with ground forces.

"We've been flying 1,000 strike sorties a day," Moseley said. "We'll continue to stack airplanes up so, in the lower stack, if you run out of gas, you go home and there's airplanes above you still with the right munitions. We have the luxury because we have air supremacy right now."

To reduce collateral damage, Moseley said, different aircraft will be armed with different munitions -- from 2,000-pound satellite-guided bombs to laser-guided Maverick missiles to 500-pound nonexplosive "cement bombs" -- so specific targets can be struck with minimum force.

Meanwhile, unmanned Predators will continue patrolling the capital at 15,000 feet and above, providing commanders with real-time video and infrared images so they can detect movements of Iraqi forces and spot emerging targets. Some of the Predators, he said, are armed with Hellfire missiles and can attack the targets they spot.

"Every day we've had Predator over the top of Baghdad looking for surface-to-air missile radars," Moseley said, "looking for missile launchers that [Hussein] has got up in the parks and some of the athletic areas, and also looking over some of the leadership targets that we struck to help us determine whether we have to re-strike it or whether we can leave it alone."

Well above the Predators, Global Hawk drones, which produce extremely high-resolution imagery, are now flying from southern Baghdad to Tikrit and Irbil in northern Iraq, he said. The Global Hawks are designed to provide hours of "persistent" reconnaissance of a target, in comparison to spy satellites in low-Earth orbit, which pass over Baghdad for only four or five minutes per orbit several times a day.

The ability of these drones and other reconnaissance aircraft to spot troop formations and moving targets and rapidly transmit that data to incoming fighters and bombers, defense officials and analysts said, has had the effect of freezing Iraqi forces in place.

"We're looking at air power that is 10 times more powerful than it was in the 1991 Gulf War," said retired Air Force Lt. Gen. Thomas G. McInerney.

By all accounts, this combination of precision strike and persistent reconnaissance had a devastating impact on Republican Guard divisions south of Baghdad, which were pounded repeatedly over the past week as the Army's 3rd Infantry Division and the 1st Marine Expeditionary Force moved north.

"I think sometimes it's very difficult for people to understand the power of air power," Maj. Gen. Victor E. Renuart Jr., director of operations for the U.S. Central Command, told reporters at headquarters in Qatar. "I don't want to sound like I'm an airman beating the air power horn, but the integration of fires from both land and air was substantial. And we were able to take advantage of superiority in the skies to prepare the battlefield."

Moseley took exception with analysts who have said that air power was "softening up" Iraqi forces. "We're not softening them up," he said. "We're killing them."

Beyond those attacks and the new close air support mission in Baghdad, Moseley said that the air war over Iraq also now includes three other components in southern, western and northern Iraq.

In the south, where British and U.S. forces are working to stabilize Basra, guard supply lines and open the flow of humanitarian goods from the port of Umm Qasr, he said, A-10 attack jets, helicopter search-and-rescue teams and cargo jets are operating from captured Iraqi air bases.

In the west, he said, a massive hunt for Iraq's mobile Scud missile launchers by Special Operations forces in tandem with bombers, fighters, helicopters, reconnaissance drones and JSTARS aircraft with ground moving-target radar has kept Hussein from firing a single medium-range ballistic missile at Israel, as he did with impunity at the beginning of the 1991 Persian Gulf War.

The Scud hunt, he said, had been rehearsed four times at Nellis Air Force Base in Nevada so commanders knew how to rapidly push data about moving targets from sensors to shooters. "I'm not willing to conclude that he can't [fire Scuds]," Moseley said. "But I'll tell you, we're closing down on the opportunities for him to get one of those things out and shoot it without us finding it."

Finally, in northern Iraq, Moseley said, U.S. warplanes are working in close conjunction with Special Operations forces, as they did during the war in Afghanistan, striking targets identified by the ground forces and attacking Iraqis along the so-called green line that divides Hussein's Iraq from the Kurdish-controlled northern sector of the country.

"Each of the fights has a certain flavor to it relative to the forces engaged," Moseley said.

During the interview with reporters at the Pentagon, Moseley revealed that a B-2 stealth bomber had flown from Whiteman Air Force Base in Missouri to attack an Iraqi barracks with 80 500-pound dumb bombs.

The B-2 was chosen, one Air Force official explained, because it can carry more such bombs than B-1 or B-52 bombers. "They created the intended effect," the official said. "In fact, I'm told there were lots of fires, which burned for hours."

Moseley also said that the "sensor-fused weapon," one of the most deadly munitions in the American arsenal, had for the first time been used in combat against Iraqi forces. This bomb is designed to pulverize tanks, light armor and troops over a 30-acre area. Each bomb dropped from an airplane releases 40 warheads equipped with laser and infrared sensors that scan the battlefield for armored vehicles and troops. The warheads then detonate either as armor-piercing slugs against armor or fragmentary steel pellets against troops.

All told, Moseley said, the U.S. military is relying on more than 50 satellites to prosecute the war in Iraq, including two dozen satellites in the Global Positioning System constellation, numerous communications satellites, about half a dozen electro-optical and radar-imaging spy satellites and an undetermined number of satellites that intercept cell phones and other ground-based communications.

Moseley also said that he had no concerns at this point in the war about running out of laser-guided or satellite-guided smart bombs. "Right now we have multiple days and multiple weeks of munitions at the expenditure rates we've been seeing over the last few days," he said.

At dusk, a formation of AH-64 Apache attack helicopters from the Army's 1st Battalion lifts off for a mission near the Shiite Muslim holy city of Najaf, almost directly due south of the capital city of Baghdad.