NEW ORLEANS - The Air Force has dropped the idea of setting up a cyber command - housed at the moment in north Louisiana - dedicated to repelling attacks on the nation's communications networks.

Instead, Air Force leaders said they would place the operations under the Air Force Space Command and create a new nuclear command.

The change of direction comes on the heels of high-profile foul-ups in the Air Force's management of the U.S. nuclear arsenal, including a mistaken shipment of four Air Force fuses for nuclear warheads to Taiwan.

The decisions "move our Air Force in the right direction," Air Force Secretary Michael Donley said in a statement Wednesday.

For the past year, the Air Force had set up a provisional command at Barksdale Air Force Base near Shreveport. The provisional command, led by a two-star general, was given a staff of about 100 and even had its own Web site. It was charged with beefing up protection of the Global Information Grid, the military's communications network.

The Barksdale command, officials have said, has been working on identifying ways the Air Force should organize, train and equip its forces to defend itself in cyberspace against an enemy.

Barksdale was a contender to permanently secure the command center, which was expected to create hundreds, if not thousands, of jobs. Barksdale, home to the 2nd Bomb Wing and the 8th Air Force, is a B-52 bomber base.

On June 5, Defense Secretary Robert Gates fired the Air Force's top leaders because of the nuclear-related missteps. At the time, Gates said he wanted to improve standards and performance in safeguarding nuclear weapons and their components.

Besides the mistaken shipment to Taiwan, in August 2007 a B-52 was mistakenly armed with six nuclear-tipped cruise missiles and flown from Minot Air Force Base, N.D., to Barksdale. The pilot and crew were unaware nuclear arms were aboard.

Sgt. Christopher DeWitt, an Air Force spokesman at Barksdale, said more details about what would happen to the cyber operations should be laid out soon.

"What will happen to the staff, we don't know," DeWitt said.

He said the Air Force has not decided where to base the new, as-yet-unnamed cyber unit.

Sen. Mary Landrieu, D-La., said the Air Force assured her Barksdale would continue to play a part in the Air Force's cyber operations.

"The Air Force is going through an organizational rough patch," Landrieu said in a statement. "However, Barksdale remains the best positioned facility to ultimately host the Air Force's cyber operation."

Landrieu said she would push the Air Force to locate both the cyber operations and the new proposed nuclear command in Barksdale. The Air Force said the nuclear command would concentrate nuclear operations.

The move away from a cyber command was met with disappointment by proponents of a more aggressive strategy to combat cyber threats from Russia, China and terrorists.

"The level of damage to the country by a cyber attack is of a sort that could cost us in the trillions of dollars," said Sami Saydjari, head of Cyber Defense Agency, an online security consulting company in Wisconsin Rapids, Wis.

"One could take out 75 percent of the power grid and hold it out for six months," he said. "It's as if a thousand (Hurricane) Katrinas hit the infrastructure and left us without police, no power, for months."

Donley, the Air Force secretary, said the Air Force would "continue to do our part to increase Air Force cyber capabilities and institutionalize our cyber mission."

DeWitt, the Barksdale spokesman, said the military remains committed to cyber warfare.

"Air Force senior leadership proved that they take the cyber threat seriously by continuing to establish some form of cyber element," DeWitt said.

Saydjari said establishing a new unit is a "a good start." But, he said, eventually the Defense Department would need to establish a command to coordinate cyber tactics across the military.

"The reality is that we have to start viewing cyberspace as a territory just as we started viewing space as a territory a few decades ago," he said. "China is ahead in the cyberspace race."