Throughout months of Republican “investigation” into the tragedy in Benghazi, Libya, on Sept. 11 last year, the Central Intelligence Agency has escaped the scrutiny and partisan bashing aimed at the State Department and the White House. But we now know that the C.I.A., and not the State Department or the White House, originated the talking points that Republicans (wrongly) insisted were proof of a scandal. It was more central to the American presence in Benghazi than the State Department, and more responsible for security there.

The C.I.A.’s role needs to be examined to understand what happened and how to better protect Americans.

Republicans have mostly fixated on the talking points that were the basis of comments made by Susan Rice, the ambassador to the United Nations, on television the Sunday after Ambassador J. Christopher Stevens and three other Americans were killed. She said the siege seemed to have been a spontaneous protest hijacked by extremists, not a planned terrorist attack. Within days, Republicans in Congress were calling for her head. They later claimed the C.I.A. wanted to tell the truth but Ms. Rice and the administration cared only about protecting President Obama.

Under pressure, the White House has since released e-mails describing the interagency machinations behind the talking points, which David Petraeus, then the C.I.A. director, initiated at the request of Representative C.A. Dutch Ruppersberger, the senior Democrat on the House Intelligence Committee. As Karen DeYoung and Scott Wilson reported in The Washington Post on Wednesday, the e-mails show that Mr. Petraeus was critical to producing talking points “favorable to his image and his agency.”