Published: Feb 07, 2013 11:24 AM EST

WASHINGTON (AP) - Defense Secretary Leon Panetta said Thursday that the speed of the attack on the U.S. Consulate in Benghazi, Libya, last September kept U.S. armed forces from responding in time to save the four Americans who were killed.
    
Testifying for likely the last time on Capitol Hill before stepping down, Panetta defended the U.S. military's response on a chaotic Sept. 11 day as the Obama administration tried to assess the threat from protests in Tunisia, Egypt, the Libyan capital of Tripoli and other countries.
    
"The United States military is not and should not be a global 911 service capable of arriving on the scene within minutes to every possible contingency around the world," Panetta said.
    
Panetta pushed back against Republican criticism that the Obama administration ignored warning signs about an attack that claimed the lives of American Ambassador Chris Stevens and three others. The Pentagon chief insisted there were no signs of or specific intelligence about an imminent attack. Six months prior to the assault, the government was apprised of 281 threats to diplomatic missions, consulates and other facilities worldwide, he said.
    
Soon after the initial attack, Panetta said, he did dispatch various military teams to Benghazi, including Marines from Spain and a special operations force that was training in Central Europe.
    
He answered emerging questions about why the U.S. didn't send more firepower, such as gunships or fixed-wing fighter jets. He said those were not in the vicinity and would have required at least nine to 12 hours to deploy. Even if aircraft could have arrived quickly, the chaos would have prevented them from getting the accurate information they needed to hit the right targets, he said.
    
"This was, pure and simple, a problem of distance and time," Panetta said.
    
Panetta testified before the Senate Armed Services Committee with Army Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff.
    
Dempsey reminded the committee that it was "9/11 everywhere" when the consulate was attacked and that U.S. armed forces were prepared to respond to a wide variety of threats around the world.
    
U.S. posts and facilities in many countries throughout Africa and southwest Asia were operating under heightened protection levels, he said.
    
"We positioned our forces in a way that was informed by and consistent with available threat estimates," Dempsey said.
    
Sen. James Inhofe, the committee's top Republican, wasted little time in criticizing the administration for trying to "cover up" what he said was clearly a terrorist attack. The U.S. ambassador to the United Nations, Susan Rice, initially attributed the violence to a protest against an American-made, anti-Islam video.
    
Rice's comments touched off a deeply partisan feud, with Republicans claiming the Obama White House wanted to obscure the reasons for the incident to help the president's re-election bid. The criticism of Rice was largely responsible for scuttling her chances to become secretary of state.
    
"An angry mob doesn't use coordinated mortars and RPGs," Inhofe said, using the acronym for rocket-propelled grenades.
    
Panetta is retiring after a Washington career that has stretched across four decades, with years as a California congressman, budget chief, White House chief of staff to President Bill Clinton and CIA director who oversaw the hunt for and killing of terrorist leader Osama bin Laden.
    
The Defense Department will bid farewell to Panetta, who has served as defense secretary since June 2011, in a ceremony on Friday. The committee gave Panetta a round of applause as Chairman Carl Levin, D-Mich., praised the Pentagon chief's integrity. President Barack Obama has nominated former Republican Sen. Chuck Hagel to succeed Panetta.
    
In his testimony, Panetta detailed the steps the military took in response to the Libya attack. He pointed out it was not a prolonged assault that the military could have ended, but rather two attacks that were short in duration and occurred about six hours apart.
    
"Despite the uncertainty at the time, however, the Department of Defense and the rest of the United States government spared no effort to save American lives," Panetta said.

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