The move is exceedingly rare and perhaps unprecedented in the history of U.S. Strategic Command, which is responsible for all American nuclear warfighting forces, including nuclear-armed submarines, bombers and land-based missiles.
The Navy's top spokesman, Rear Adm. John Kirby, said Giardina, who had held the job since December 2011, is being reassigned to the Navy staff pending the outcome of the probe by the Naval Criminal Investigative Service. The gambling matter originated as a local law enforcement investigation in Iowa in June.
As a consequence of being removed from his post at Strategic Command, Giardina falls in rank to two-star admiral. He had been suspended by Gen. Robert Kehler, the top commander at Strategic Command, on Sept. 3, although that move was not disclosed publicly until Sept. 28.
After his suspension Giardina remained at Strategic Command but was not allowed to perform duties that required use of his security clearance.
The decision to take the next step -- to relieve him of duty -- was made on Oct. 3, one official said. That required approval by President Barack Obama, two defense officials said. The officials spoke on condition of anonymity because they were not authorized to publicly discuss the internal decision-making.
Kehler had recommended to Defense Secretary Chuck Hagel that Giardina be relieved of duty and returned to the Navy, and Hagel agreed, according to Pentagon spokesman Carl Woog.
Giardina had no comment Wednesday, according to a Strategic Command spokeswoman, Navy Capt. Pamela Kunze.
A former commander of Strategic Command, retired Air Force Gen. Eugene Habiger, said he believes this is the first time in the history of the command that a deputy commander has been relieved of duty. Strategic Command was created in 1992 at the end of the Cold War. The aim was to unify the command of nuclear forces previously run separately by the Air Force and the Navy.
"I know of no other case ever of a deputy commander who was relieved for cause," Habiger said in a telephone interview. He headed the command from 1996-98.
Giardina is a career submarine officer. He commanded Submarine Squadron 17 in Bangor, Wash., which included 10 nuclear-armed Trident submarines from 2001-03. He is a 1979 graduate of the U.S. Naval Academy and holds an advanced degree in business administration.
Iowa state officials have said Giardina is alleged to have used $1,500 in counterfeit chips at the Horseshoe Casino in Council Bluffs, Iowa, across the Missouri River from Strategic Command headquarters near Omaha, Neb. He has not been charged with a crime.
In July the White House nominated Air Force Lt. Gen. James Kowalski to succeed Giardina as deputy commander at Strategic Command, but his nomination has not been confirmed by the Senate.
Kowalski has overseen the Air Force's nuclear bomber and intercontinental ballistic missiles forces since January 2011 as commander of Air Force Global Strike Command at Barksdale Air Force Base, La.
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