The highly critical report also says the U.S. military was not positioned to aid the Americans in need, though the head of Africa Command had offered military security teams that Stevens — who was killed in the attack — had rejected weeks before the attack.
It also said that in the aftermath of the attacks, U.S. analysts confused policymakers by blaming the violence on protests without enough supporting intelligence.
The 2012 Benghazi attacks have dogged the Obama administration, because then-U.N. Ambassador Susan Rice initially blamed the violence on mob protests over an anti-Islamic film. Al-Qaida-linked militant groups were later blamed for the attacks, first when militants overran the temporary U.S. mission on Sept. 11, 2012, and later that same night, when militants fired mortars at the nearby CIA annex where the Americans had taken shelter.
The bipartisan report may settle what has become a running political battle between Republicans, mostly in the House, who say the Obama administration has been covering up what they consider misdeed before, during and after the attack, and the administration, which says Republicans are on a political witch hunt.
Committee chairman Dianne Feinstein, a California Democrat, says she hopes this will put to rest conspiracy theories about the militant attacks that night. Republican vice chairman Saxby Chambliss of Georgia said the report shows despite a deteriorating security situation in Benghazi, the U.S. government did not do enough to prevent the attacks or to protect the diplomatic facility.
"The State Department should have increased its security posture more significantly in Benghazi based on the deteriorating security situation on the ground and IC threat reporting on the prior attacks against Westerners in Benghazi_including two previous incidents" at the temporary diplomatic facility that year, a summary of the report states.
The State Department said Wednesday that there have been dozens of reports, hearings and briefings on the Benghazi attack and that many of the Senate Select Committee on Intelligence's findings are similar to those made by the independent Benghazi Accountability Review Board, which issued a report in December 2012.
The Senate report does note that the State Department has created a new assistant secretary position for high threat posts to focus on such dangerous areas, but says the department should in the future react more quickly to security threats and only in rare instances use facilities that are inadequately protected. It said State should not rely on local security alone in countries where the host government cannot provide adequate protection.
The report notes that the State Department in 2012 had ignored its own "tripwires" set to determine when it had become too dangerous to operate in Benghazi, and continued to operate the facility there, despite a steady drumbeat of U.S. intelligence reports showing the danger was rising.
The report faults the military for being unable to help when needed. "No U.S. military resources in position to intervene in short order in Benghazi to help defend" the U.S. facilities in Benghazi, it said.
Yet it points out that Stevens had rejected additional security. The Defense Department had provided a Site Security Team in Tripoli, made up of 16 special operations personnel to provide security and other help. The State Department, according to the report, decided not to extend the team's mission in August 2012, one month before the attack. In the weeks that followed, Gen. Carter Ham, the head of Africa Command, twice asked Stevens to employ the team, and twice Stevens declined, the report said.
The report also dives into the contentious talking points issued by the intelligence community after the attacks that helped fuel Republican allegations of an Obama administration cover-up of militant links to the violence.
"Intelligence analysts inaccurately referred to the presence of a protest at the U.S. mission facility before the attack based on open source information and limited intelligence, but without sufficient intelligence or eyewitness statements to corroborate that assertion," the report said, adding that the U.S. intelligence community then took too long to correct their error, "which caused confusion and influenced the public statements of policymakers."
It also says the intelligence community should expand its mining of social media to watch for unrest, and also draw more heavily on eyewitness reporting "especially from U.S. government personnel_in the aftermath of a crisis."
The senators also take the administration to task for failing to bring the attackers to justice more than a year after the Benghazi attacks.
It says U.S. intelligence has identified several individuals responsible, but can't track them down because of limited intelligence capabilities in the region.
White House spokesman Jay Carney said the committee report "largely reaffirms" the earlier findings from an independent panel. He said a number of the committee's security recommendations are also consistent with steps the State Department has already taken.
"This reinforces what other investigations have found, which is that there was not enough security to protect the four Americans who lost their lives," Carney told reporters traveling with Obama Tuesday to North Carolina.
AP Writers Julie Pace and Deb Riechmann contributed to this report.
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