A new report from the State Department blames "systemic failures" and "management deficiencies" for allowing U.S. diplomats to operate in Libya with less security than was needed, allowing an attack on September 11, 2012 to result in the deaths of four Americans, including the U.S. Ambassador.

The 39 page report released on Tuesday night did not include any recommendations for disciplinary action though against any State Department employees, even as the review leveled sharp criticism over the security lapse.

"However, the Board did not find that any individual U.S. Government employee engaged in misconduct or willfully ignored his or her responsibilities, and, therefore did not find reasonable cause to believe that an individual breached his or her duty so as to be the subject of a recommendation for disciplinary action," the unclassified report concluded.

The report, which can be found here, begins with a quote from George Santayanna's famous 1905 line, "Those who cannot remember the past are condemned to repeat it."

The investigation found that security in Benghazi "was inadequate, despite repeated requests from Special Mission Benghazi and Embassy Tripoli for additional staffing."

Also complicating matters was that the Benghazi mission seemed to fall between the cracks in the State Department.

"Among various Department bureaus and personnel in the field, there appeared to be very real confusion over who, ultimately, was responsible and empowered to make decisions based on both policy and security considerations," the report found.

The unclassified report runs down a series of incidents in Benghazi which indicated a security situation that was somewhat tenuous for Westerners, but that did not trigger additional assistance for U.S. diplomats.

The report included a first-person account of how a mob attacked the U.S. consulate in Benghazi - but not in September of 2012 - in June of 1967, during an outbreak of violence related to the Arab-Israeli conflict.

The report details what happened on September 11, the bravery of CIA agents who tried to protect the U.S. Ambassador, and their efforts to safeguard other Americans while being attacked repeatedly in the streets of Benghazi.

Here are the five main findings from the report:

1. The attacks in Benghazi were security-related, resulting in the deaths of four U.S. personnel after terrorists attacked two separate U.S. government facilities – the Special Mission compound (SMC) and the Annex.

2. Systemic failures and leadership and management deficiencies at senior levels within two bureaus of the State Department resulted in a Special Mission security posture that was inadequate for Benghazi and grossly inadequate to deal with the attack that took place.

3. Notwithstanding the proper implementation of security systems and procedures and remarkable heroism shown by American personnel, those systems themselves and the Libyan response fell short in the face of a series of attacks that began with the sudden penetration of the Special Mission compound by dozens of armed attackers. In short, Americans in Benghazi and their Tripoli colleagues did their best with what they had, which, in the end, was not enough to prevent the loss of lives of Ambassador Stevens, Sean Smith, Tyrone Woods, and Glen Doherty.

4. The Board found that intelligence provided no immediate, specific tactical warning of the September 11 attacks. Known gaps existed in the intelligence community’s understanding of extremist militias in Libya and the potential threat they posed to U.S. interests, although some threats were known to exist.

5. The Board found that certain senior State Department officials within two bureaus in critical positions of authority and responsibility in Washington demonstrated a lack of proactive leadership and management ability appropriate for the State Department’s senior ranks in their responses to security concerns posed by Special Mission Benghazi, given the deteriorating threat environment and the lack of reliable host government protection. However, the Board did not find that any individual U.S. Government employee engaged in misconduct or willfully ignored his or her responsibilities, and, therefore did not find reasonable cause to believe that an individual breached his or her duty so as to be the subject of a recommendation for disciplinary action.