Thanks to alex perez. We turn to hillary clinton. Her final step as secretary of state comes today, when she introduces john kerry. And that is after her testimony about the attack in benghazi that... See More
Thanks to alex perez. We turn to hillary clinton. Her final step as secretary of state comes today, when she introduces john kerry. And that is after her testimony about the attack in benghazi that killed a u.S. Ambassador and three other americans. Martha raddatz was there for all of the action. Good morning, martha. Reporter: Good morning, george. It was truly a riveting day on capitol hill. We don't say that very often, with secretary clinton. In a way that some have never seen her before. She was at times, combative, charming, disarming and clearly ready for a fight. It is our job to figure out what happened and do everything we can to prevent it from ever happening again, senator. Reporter: When clinton spoke of her four fallen colleagues, the pain, the memories were still raw. I stood by president obama as the marines carried the flag-draped caskets off the planes at andrews. I put my arms around the mothers and fathers, the sisters and brothers. Reporter: And clinton did not hesitate to shoulder the blame. I said many times, I take the responsibility. Reporter: That did little to quiet some republicans, who wanted to know how this could have happened. Had I been president at the time, I would have relieved you of your post. I think it's inexcusable. Reporter: The secretary fought back, aggressively defending comments made by u.N. Ambassador susan rice five days after the attack. A very simple phone call to these individuals would have ascertained immediately, there was no protest. With all due respect, the fact is, we have four dead americans. Was it because of a protest? Or because of guys out for a walk that decided to go kill some americans? What difference at this point does it make? Reporter: A strong defense that did not satisfy senator john McCain. Why do we care? Because if the classified information had been included, it gives an entirely different version of events. Reporter: Like mccain, there were some republicans who convince. But this was certainly a memorable way to close out her tenure, george. And a memorable day, today, coming up, martha. The ban on women in combat going to be formally lifted by leon panetta. It will be a big part of his legacy. But it's something that's being pushed hard by the military, the joint chiefs of staff. Reporter: It was the joint chiefs, the marine, the army and other services. It reflects the reality of the last decade of war. Well more than 100 women have died in iraq and afghanistan, where the front lines have blurred. It does take it to a new level. They could officially be part of infantry units and special forces, if they meet the physical standard. That means more women in top leadership positions in the military, as well. Reporter: That's what it could mean. And there's soldiers that are worried about this. But change is hard. Let's get our top stories from bill weir.
This transcript has been automatically generated and may not be 100% accurate.