WASHINGTON — Senior Air Force leaders are creating a new command to better manage the nation's nuclear arsenal after a series of embarrassing missteps in the handling and oversight of its most sensitive materials.

Air Force Secretary Michael Donley told reporters Friday that the service is shifting its nuclear-capable bombers, missiles and staff into a new Global Strike Command. So far officials have spent more than $200 million on the reorganization effort, and expect to spend another $270 million during the fiscal year that began Oct. 1. But Air Force leaders could not provide a total cost or staffing for the new command, which will be led by a three-star general.

One of the major blunders involved the mistaken shipment to Taiwan of four electrical fuses for ballistic missile warheads. The shipment was supposed to have been replacement helicopter batteries. The fuses originated from F.E. Warren Air Force Base in Cheyenne, Wyo., in March 2005, when they were shipped to a Hill Air Force Base warehouse. Sometime around August 2006, the shipment was delivered to Taiwan. The mistake wasn't realized until March, and the fuses were quickly recovered.

Various generals, including Maj. Gen. Kathleen Close, commander of the Ogden Air Logistics Center, were reprimanded.

The other blunder involved the flight of an Air Force B-52 bomber that was mistakenly armed with six nuclear-tipped cruise missiles and flown from Minot Air Force Base, N.D., to Barksdale Air Force Base, La. At the time, the pilot and crew were unaware they had nuclear arms aboard.

Donley said the latest shuffle would be a "new starting point" that would reinvigorate the service's nuclear mission. And he said it would help the Air Force focus on the management of the arsenal, no matter how small it may become under future international agreements.

The idea for a new, separate command stemmed from a recent highly critical report that concluded there has been a decline in the Air Force's focus on and performance of its nuclear mission and its leaders' failure to respond effectively.

Planned changes involve improved inspections, more emphasis on nuclear expertise, and a better coordinated system to track nuclear materials. Control of the B-2 and B-52 bombers now under Air Combat Command, and the intercontinental ballistic missiles now under Space Command, will shift to the newly formed Global Strike Command.

While largely bureaucratic in nature, the changes reflect a realization by the Air Force that in this post-Cold War era, attention to the nuclear mission had slipped and must now be corrected. But it took a series of embarrassing incidents that eventually prompted Defense Secretary Robert Gates to fire the previous Air Force secretary and chief of staff.

A Pentagon advisory group, in a review of the problems, recommended last month that nuclear responsibilities be coordinated under the already existing Space Command, which is responsible for the service's land-based nuclear missiles but not other nuclear weapons.

Asked why officials chose to create a new command rather than follow the group's recommendation, Air Force Chief of Staff, Gen. Norton Schwartz, said officials believed that lumping all the responsibility for space, cyber and nuclear issues would be too much for one command.

Contributing: Joseph M. Dougherty, Deseret News