Updated at 10:50 p.m. ET: An independent panel's sharply critical report on the Sept. 11 attacks on the Benghazi consulate blames "systemic failures and leadership and management deficiencies within two bureaus of the State Department" for the post's inability to defend itself. 

The report details the events that unfolded on Sept. 11 in Benghazi, Libya, when the Special Mission post was overrun by militants who used rocket-propelled grenades, mortars and machine-gun fire, according to the 39-page report. Ambassador Christopher Stevens and three other Americans were killed.

The report's findings fall largely into two categories: staffing and the physical security of the Benghazi post. Staff was, according to the report, talented but relatively inexperienced. Personnel there spent about 40 days on assignment, resulting in "diminished institutional knowledge." 

In a statement Tuesday, U.S. Secretary of State Hillary Clinton said she accepts the report's recommendations. The independent review board was formed at her request and was chaired by former Joint Chiefs Chairman Mike Mullen and former Ambassador Tom Pickering. 

In addition to staffing issues, the report says that Ambassador Stevens "made the decision to travel to Benghazi independently of Washington, per standard practice." 

Further, the report says, Embassy's country team was not fully aware of Stevens' movements off the compound.

Stevens' "status as the leading U.S. government advocate on Libya policy, and his expertise on Benghazi in particular, caused Washington to give unusual deference to his judgments." 

Stevens arrived in Benghazi on a Greek cargo ship on April 5, 2011, according to the report. American embassy personnel had been evacuated months before, in February. At the time, Stevens was a special envoy to the Libyan Transitional National Council.

Stevens was the report says, "extremely effective" and admired by Libyans. He "personified the U.S. government commitment to a free and democratic Libya."  

Against a backdrop of mounting political violence, Benghazi became less secure, the report points out in the form of a timeline. The timeline begins with an armed robbery that took place at the British School on March 18 and ends with a small bomb thrown at an Egyptian diplomat's car on Aug. 20. 

Stevens arrived in Benghazi on Sept. 10, accompanied by two temporary duty officers. Security staffing at the post on the day of the attack was inadequate and did not meet security standards, according to the report. 

The report states strongly that Congress must meet budgetary challenges to "provide necessary resources to the State Department." Specifically, Congress should restore a security program to $2.2 billion by 2012.

Managers, the report says, have become conditioned to tightening the purse strings. 

That said, the report continues, the Embassy in Tripoli did not advocate enough for increased security at the Benghazi post. Some security upgrades had been made, although they were not sufficient, including safety grills on windows, concrete jersey barriers and some locally-manufactured steel doors. 

As a result, the report says on its first page, "systemic failures and management deficiencies" rendered the Special Mission post in Benghazi "grossly inadequate to deal with the attack."  

And although it found that "certain senior State Department officials within two bureaus demonstrated a lack of proactive leadership" when Benghazi asked for more protection, the report said that no employees breached their duty.

The report, although critical, addresses the difficulties faced. Terrorist and hostile actors posing threats to American security are "growing" and "diffuse," it says. Resorting to a "total fortress and stay-at-home approach to U.S. diplomacy" would be unacceptable. 

Recommendations
The report recommends that the U.S. should strengthen security in high-risk posts beyond what is provided by host governments and lean on outside experts to regularly assess security at the posts. The State Department should also reorganize its Bureau of Diplomatic Security and appoint an official charged with overseeing high threat posts. 

The State Department should also boost Marine security and hire more diplomatic security personnel at high-risk posts, the report said. 

The State Department should also improve language abilities, particularly Arabic, among employees, the report says.  

Testifying
Mullen and Pickering are scheduled to brief congressional committees on the classified version of the report on Wednesday. Hearings on the report are scheduled in the Senate and the House on Thursday. 

Clinton was supposed to testify in hearings on the report on Thursday but she remains at home recovering from a bout with the flu that resulted in her fainting and suffering a concussion. 

Her two deputies, William Burns and Thomas Nides, will testify in her place. 

Debate over the attacks polarized Republican and Democratic lawmakers, as Republicans questioned whether the consulate had adequate security and whether the State Department had responded to requests for more protection. 

At the same time, U.S. spy agencies produced conflicting reports on who was behind them, U.S. officials have said. Most said extremists with possible al-Qaida ties were involved. But a few reports, which the Obama administration emphasized in early public statements, said the attacks could have been spontaneous protests against an anti-Muslim video made in the U.S.

United Nations Ambassador Susan Rice faced intense criticism from Republican lawmakers when she made comments indicating that the attacks were a spontaneous response to a low-budget movie made in the U.S. that maligned the Islamic Prophet Mohammed. She later said she had not meant to be misleading but was relaying intelligence that she had been provided. 

Rice dropped out of the running for secretary of state, citing the "very politicized confirmation process."

NBC's Catherine Chomiak and Reuters contributed reporting.

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By Tracy Connor, NBC News

Embattled U.N. envoy Susan Rice is dropping out of the running to be the next secretary of state after months of criticism over her Benghazi comments.

“Today, I made the decision that it was the best thing for our country, for the American people that I not continue to be considered by the president for nomination of secretary of state,” Rice told NBC’s Brian Williams.

“I didn’t want to see a confirmation process that was very prolonged, very politicized, very distracting and very disruptive because there are so many things we need to get done as a country and the first several months of a second term president’s agenda is really the opportunity to get the crucial things done.”

Rice noted that President Obama’s second-term agenda included “comprehensive immigration reform, balanced deficit reduction, job creation.”

She added, “And to the extent that my nomination could have delayed or distracted or deflected or maybe even some of these priorities impossible to achieve, I didn’t want that and I much prefer to keep doing what I’m doing which is a job I love at the United Nations.”

The full interview with Rice will air on tonight’s “Rock Center With Brian Williams” at 10p/9c. Excerpts will also be broadcast on Nightly News at 6:30 pm ET.

Obama said in a statement that he accepted her decision and regretted “the unfair and misleading attacks” on Rice, who was considered a front-runner to replace Hillary Clinton as the nation’s top foreign policy official.

Criticism over remarks
Rice has been under intense fire from Republicans for initially characterizing the Sept. 11 assault on the U.S. consulate in Benghazi, Libya, as a spur-of-the-moment response to a crude anti-Muslim film.

“What happened in Benghazi was in fact initially a spontaneous reaction to what had just transpired hours before in Cairo, almost a copycat of the demonstrations against our facility in Cairo, which were prompted, of course, by the video,” Rice said on NBC’s “Meet the Press” five days after the attack.

“Opportunistic extremist elements came to the consulate as this was unfolding. They came with heavy weapons, which unfortunately are readily available in post-revolutionary Libya, and it escalated into a much more violent episode.”

As more details emerged suggesting it was a premeditated terrorist action, GOP critics accused Rice of misleading the public at the height of the presidential campaign.

She countered that she went with the best information available about the attack, in which Ambassador Chris Stevens and three other Americans were killed.

“I relied solely and squarely on the information provided to me by the intelligence community. I made clear that the information was preliminary and that our investigations would give us the definitive answers,” she said on Nov. 21 at the United Nations.

By then, Obama had already expressed strong support for Rice, warning Sens. John McCain (R-Ariz.) and Lindsey Graham (R-S.C.) to stop slamming her and vowing to block her confirmation.

“They should go after me,” he said at his first press conference after his re-election.

Despite a series of closed-door meeting with Capitol Hill lawmakers to drum up support, Rice continued to face questions from senators key to her confirmation.

After a Nov. 28 sitdown with Rice, Sen. Susan Collins (R-Maine) said she couldn’t yet endorse the veteran diplomat and raised a new point of concern: her role in protecting American embassies in Kenya and Nairobi that were bombed by terrorists in 1998.

Sen. Bob Corker (R-Tenn.) suggested Rice was seen as too much of an Obama loyalist and the GOP preferred “someone of independence.”

Attack on critics
In her resignation letter to Obama, Rice took aim at her GOP critics.

“The position of secretary of state should never be politicized,” she wrote.

“As someone who grew up in an era of comparative bipartisanship and as a sitting U.S. national security official who has served in two U.S. Administrations, I’m saddened that we have reached this point, even before you have decided whom to nominate. We cannot afford such an irresponsible distraction from the most pressing issues facing the American people.”

Obama praised Rice as “an extraordinarily capable, patriotic, and passionate public servant.”

“While I deeply regret the unfair and misleading attacks on Susan Rice in recent weeks, her decision demonstrates the strength of her character, and an admirable commitment to rise above the politics of the moment to put our national interests first.”

McCain and Graham, among Rice’s loudest critics, said they would continue to press the administration on Benghazi.

“I respect Ambassador Rice’s decision,” Graham said in a statement. “President Obama has many talented people to choose from to serve as our next secretary of state.”

The withdrawal leaves Sen. John Kerry (D-Mass.) as a possible candidate for the job, and Republicans have said he would have a smoother run.

"I think John Kerry would be an excellent appointment and would be easily confirmed by his colleagues," Collins said last month.

Rice, 48, has been the United States’ permanent representative to the United Nations since 2009, after serving as a senior advisor to the Obama campaign, working at the Brookings Institution and holding other diplomatic and national security positions dating back to 1993.

UNITED NATIONS – U.N. Ambassador Susan Rice on Wednesday defended her remarks on a September attack in Benghazi, Libya, that killed four Americans, including the U.S. ambassador to the North African nation.

Republicans have criticized Rice, seen as a possible nominee to replace Secretary of State Hillary Clinton, for appearing on several TV talk shows five days after the Sept. 11 attack on the U.S. diplomatic mission in Benghazi and saying that preliminary information suggested the assault was the result of protests over an anti-Muslim film, rather than a premeditated strike.

“I relied solely and squarely on the information provided to me by the intelligence community. I made clear that the information was preliminary and that our investigations would give us the definitive answers," Rice told reporters at the United Nations in her first comments on the controversy.

The U.S. ambassador to Libya, Christopher Stevens, and three other Americans were killed in the attack, which has raised questions about security of diplomatic missions, U.S. intelligence about the threat, and the adequacy of the immediate response.

"Everyone, particularly the intelligence community, has worked in good faith, to provide the best assessment based on the information available," Rice said. "None of us will rest ... until we have the answer and the terrorists responsible for this attack will be brought to the justice."

Senate Republicans John McCain and Lindsey Graham vowed last week to oppose any attempt by President Barack Obama to elevate Rice to a Cabinet position that would require Senate confirmation.

Rice said that while she had "great respect" for McCain, some statements that he made about her "are unfounded" and that she looked forward to have an opportunity to discuss the issue with him.

The White House has also said that Rice's comments were based on the best information she had at the time.

Sen. Carl Levin, the Democratic chairman of the Senate Armed Services Committee, said on Sunday that the Rice had been "using the unclassified talking points which were provided by the intelligence community."

NBC News chief foreign affairs correspondent Andrea Mitchell contributed to this report from Reuters.

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Updated at 4:44 p.m. ET: President Barack Obama on Wednesday spiritedly defended U.N. Ambassador Susan Rice over her response to the September attack on the U.S. mission in Benghazi, Libya, that left four Americans dead, assailing Republican criticism of her as "outrageous."

At his first news conference since winning re-election, the president said Rice has done “exemplary work” and accused GOP critics of trying to “besmirch” her reputation.

“I don’t think there’s any debate in this country that when you have four Americans killed, that’s a problem, and we’ve got to get to the bottom of it and there needs to be accountability. We’ve got to bring those who carried it out to justice. They won’t get any debate from me on that,” Obama said sternly.

“But when they go after the U.N. ambassador, apparently because they think she’s an easy target, then they’ve got a problem with me.”

Two of Rice’s main GOP critics refused to back down.

Sen. Lindsey Graham said shortly after Obama’s news conference that he had “no intention of promoting anyone who is up to their eyeballs in the Benghazi debacle.” Sen. John McCain added: "We owe the American people and the families of the murdered Americans a full and complete explanation, which for two months the President has failed to deliver.”

Bebeto Matthews / AP file

U.S. Ambassador Susan Rice speaks during a meeting on Syria in the United Nations Security Council, Aug. 30.

Rice has been mentioned as a possible successor to U.S. Secretary of State Hillary Clinton, who has said she will not continue to serve in Obama's second term beginning in January.

Senior Republican senators vowed earlier on Wednesday to block any future promotion of Rice, questioning her initial description of the Sept. 11 violence on the U.S. consulate in Benghazi as a spontaneous outburst rather than a planned attack as unfathomable. Killed in the violence were U.S. Ambassador Chris Stevens and three other American officials.

“My judgment at this time is that four Americans were killed, and the information that our U.N. ambassador conveyed was clearly false," McCain, R-Ariz., the top GOP senator on the Armed Services Committee, told reporters at a Capitol Hill news conference. "There was overwhelming evidence that it was completely false. And she should have known what the situation and circumstances were and not tell the world on all Sunday morning talk shows.” 

Graham, of South Carolina, supported that stance at the same news conference, saying of Rice, "I don't trust her. And the reason I don't trust her is because I think she knew better, and if she didn't know better, she shouldn't be the voice of America.”

The two lawmakers along with Sen. Kelly Ayotte of New Hampshire are pressing for a special, Watergate-style select Senate committee to investigate the Benghazi attack. They complained that separate inquiries by various Senate panels will fail to get to the bottom of the deadly incident.

Rice has been the focal point of accusations that the Obama administration misled the public about the nature of the Benghazi attack. Five days after the attack, she appeared on several news talk programs and said the attack stemmed from outrage in the Arab world over an anti-Muslim video, not an act of terrorism. The White House later corrected that claim.

Obama wouldn’t comment on whether he’d nominate Rice to replace Clinton on his Cabinet. But he said of Rice: “She has done exemplary work.”

“She made an appearance at the request of the White House in which she gave her best understanding of the intelligence (on Benghazi) that had been provided to her. If Sen. McCain and Sen. Graham and others want to go after somebody, they should go after me – and I’m happy to have that discussion with them," he said animatedly.

“But for them to go after the U.N. ambassador, who had nothing to do with Benghazi and was simply making a presentation based on intelligence that she had received, and to besmirch her reputation, is outrageous.”

Shortly after the president’s remarks, Graham issued the following statement:

“Mr. President, don’t think for one minute I don’t hold you ultimately responsible for Benghazi.  I think you failed as Commander in Chief before, during, and after the attack. 

We owe it to the American people and the victims of this attack to have full, fair hearings and accountability be assigned where appropriate. Given what I know now, I have no intention of promoting anyone who is up to their eyeballs in the Benghazi debacle.”

McCain said initial Obama administration statements the the Benghazi attack was triggered by a spontaneous demonstration and a hateful video “clearly did not comport with the facts on the ground.“

In a statement issued after Obama’s news conference, McCain repeated his call for a select committee to be appointed “to obtain a full and complete accounting which would be credible with the American people."

Not all Republican senators agree with the the need for a special select committee.

Sen. Susan Collins, R-Maine, said she did not “see the benefit” of such an approach, noting the Homeland Security Committee has governmentwide jurisdiction and “a history of producing comprehensive bipartisan reports.”

Sen. Joe Lieberman, I-Conn, said assigning the matter to a select committee at this point would be “premature.”

David Petraeus, who stepped down as CIA director last week after acknowledging an extramarital affair, has agreed to testify before Congress on the Benghazi attack. He'll go before the Senate Intelligence Committee on Thursday and the House committee on Friday.

Rep. Dutch Ruppersberger, D-Md., the ranking member on the House Intelligence Committee, said Wednesday that he would like to hear from Petraeus but has yet to formally request a meeting with him.

NBC News Capitol Hill Correspondent Kelly O’Donnell and NBC News Associate Producer Catherine Chomiak contributed to this report.

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The attack that killed four Americans at the U.S. Consulate in Benghazi, Libya, apparently began as a spontaneous protest against an anti-Islam film before turning violent, Susan Rice, U.S. ambassador to the United Nations, said Sunday.

Rice, appearing in NBC’s “Meet the Press,” said she was citing preliminary information and that the FBI was investigating the Tuesday night attack that killed the U.S. ambassador to Libya, Chris Stevens, and three others.

A wave of protests and violence has swept across the Middle East and elsewhere in the Muslim world over an obscure, amateurish movie called "Innocence of Muslims" that depicts Muhammad as a fraud, a womanizer and a pedophile. Anti-U.S. protests in 20 countries led the Pentagon to dispatch elite Marine antiterrorism teams to Libya and Yemen and to position two Navy warships off Libya's coast.

Meanwhile, the State Department ordered all nonessential U.S. government workers and their families out of Sudan and Tunisia. In Lebanon, protesters torched an American fast-food restaurant. Even as tensions appeared to ease over the weekend, al-Qaida's most active Mideast branch was calling for further attacks on U.S. embassies.

"There's no question, as we've seen in the past with things like 'The Satanic Verses,' with the cartoon of the Prophet Muhammad, there have been such things that have sparked outrage and anger and this has been the proximate cause of what we've seen," Rice said.

“What happened in Benghazi was in fact initially a spontaneous reaction to what had just transpired hours before in Cairo, almost a copycat of the demonstrations against our facility in Cairo, prompted by the video,” Rice said.

More from "Meet the Press": Israeli PM tries to strike more neutral pose in U.S. election 

Protesters in Cairo had breached the walls of the U.S. Embassy and tore down the American flag.

In Benghazi, Rice told “Meet the Press” host David Gregory, “Opportunistic extremist elements came to the consulate as this was unfolding, they came with heavy weapons, which unfortunately are readily available in post-revolutionary Libya, and it escalated into a much more violent episode.”

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There was “no actionable intelligence” that the attack in Benghazi was imminent, Rice said. The attack overwhelmed security in place at the consulate, she said.

Rice’s comments came a day after Libyan President Mohammed Magarief told NBC News that “foreigners” were involved in the planning and execution of the attack.

He expanded on the assertion Sunday, saying on CBS’ "Face the Nation" that about 50 people, not all Libyans, have been arrested in connection with the Benghazi attack, which he said was planned by al-Qaida-linked foreigners, some from Mali and Algeria.

Magarief said there was little doubt the assault was planned rather than a spontaneous reaction to the video, as came on the 11th anniversary of the 9/11 terrorist attacks in the U.S.

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He said the security situation in Libya remained "difficult" for Americans, as well as for Libyans. The United States wants the FBI to investigate the consulate attack, but Magarief said it may be too soon to send in investigators.

"It may be better for them to stay away for a little while until we do what we have to do ourselves," he said.

Rice told "Meet the Press" that the U.S. is working with authorities in Libya, which has received $200 million in U.S. aid since 2011, to bring to justice those responsible for the attack.

This article includes reporting by Reuters.

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Reuters

Updated at 5:50 p.m. ET: Secretary of State Hillary Clinton said on Tuesday that North Korea's planned rocket launch this week would violate U.N. Security Council resolutions and Pyongyang should forgo it if it wants a better future.

“I would just underscore that if North Korea wants a peaceful, better future for their people, it should not conduct another launch that would be a direct threat to regional security,'' she told reporters in Washington after talks with Japanese Foreign Minister Koichiro Gemba.

Gemba said Japan, a key U.S. ally, would cooperate with Washington and the international community in framing its response.

Russia, too, on Tuesday criticized North Korea.

"We consider Pyongyang's decision to conduct a launch of a satellite an example of disregard for U.N. Security Council decisions," state-run news agency RIA quoted Russian Foreign Ministry spokesman Alexander Lukashevich as saying.

"It is necessary to seek a way out of the situation on the political-diplomatic track," he said. 

Earlier Tuesday, U.S. Ambassador to the United Nations Susan Rice said the U.N. Security Council should agree on a credible response if North Korea flouts U.N. resolutions banning Pyongyang from using ballistic missile technology.

NBC's Richard Engel answers reader questions from Pyongyang, North Korea

"Should it occur, the council will need to convene and to respond credibly," Rice, president of the 15-nation council this month, told reporters. "There is no disagreement among members of the Security Council that this is a provocative act."

North Korea: Our rocket is ready to launch

Space officials in North Korea told NBC Tuesday that all assembly and preparations for its new satellite and rocket have been completed. The launch will be sometime between Thursday and Monday, they said.

Speaking at a press conference in the capital, Pyongyang, the experts refused to answer the question about whether the rocket has been fueled yet, but they said assembly and other preparations are done.

They also repeated their insistence that that satellite is not a cover for a missile test, adding that "the right to have a satellite is a universal right of every nation."

Regarding U.S. concerns, the official said, "These are things that shouldn't be worried about."

Reuters, The Associated Press and NBC's Ed Flanagan contributed to this report.

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