The State Department’s so-called Accountability Review Board failed to hold anyone accountable. According to reports, the ARB found “systemic failures” led to the attack at the US consulate in Benghazi, Libya on Sept. 11, 2012.

The report, posted Tuesday night on the State Department’s website, also identified “leadership and management deficiencies at senior levels within two bureaus.” It suggested 29 ways the department can improve its operations, but recommended no disciplinary action.

So much for accountability.

The board at least did manage to confirm that there was no protest at the consulate leading up to the assault.

Although the motive for the attack remains unclear, the report released Tuesday confirms what quickly became evident — that the attack was the coordinated work of heavily armed terrorists.

The report confirmed that the attack involved “arson, small arms and machine gun fire, and the use of RPGs, grenades, and mortars.”

While also blaming State Department personnel for the security situation without naming them, the report focuses some of its fire on the Libyans hired to provide security at the compound.

Think about that for a second, though. Who hired those Libyans to provide security at the consulate? Who in their right mind thought that decision could possibly end well?

The board’s recommendations could have been written by any Captain Obvious in Washington.

Among the board’s recommendations for the State Department are to strengthen its security detail in high-risk posts, to build more-secure facilities, to request the support of additional Marines and to step up security training.

Clinton’s convenient concussion means we’ll probably never find out exactly why Ambassador Christopher Stevens was in Benghazi that night, why the consulate’s requests for security were repeatedly rebuffed, and why she and President Obama and Ambassador Susan Rice blamed the attack on a movie.

Update: The AP reports that the State Department’s security chief and two other officials have resigned in the wake of the Benghazi report’s release.