And now, we turn to the fiery appearance for secretary of state hillary clinton, testifying before congress on the tragedy in benghazi. It was indignation and emotion as she ends this tenure on the... See More
And now, we turn to the fiery appearance for secretary of state hillary clinton, testifying before congress on the tragedy in benghazi. It was indignation and emotion as she ends this tenure on the public stage. Abc's chief global affairs correspondent martha raddatz brings us the riveting encounter today. Martha? Reporter: Diane, what a way to end her four-year tenure as secretary of state. A month ago, she was flat on her back with a nasty concussion, prompting accusations she was trying to avoid testifying about benghazi. But today, this woman who has traveled the world as america's top diplomat came to the hill ready for a fight. It was a riveting drama. Secretary of state clinton seen in rare public form, at times angry, aggressively on the defense. At another point, choking up over her four lost colleagues. For me, this is not just a matter of policy, it's personal. I stood next to president obama as the marines carries those flag-draped caskets off the plane at andrews. I put my arms around the mothers and fathers, the sisters and brothers, the sons and daughters and the wives left alone to raise their children. The american people and the families of these four brave americans still have not gotten the answers that they deserve. I hope that they will get them. Reporter: And the secretary did not hesitate to shoulder the blame. The buck, she said, stopped with her. As I have said many times, i take responsibility and nobody is more committed to getting this right. Reporter: But she insisted she never saw any of the requests for more security in the runup to the attack. They didn't come to me, i didn't approve them, I didn't deny them. Reporter: That made republican senators pounce. Had I been president at the time and I found that you did not read the cables from benghazi, you did not read the cables from ambassador stevens, I would have relived you of your post. Reporter: Clinton fired back in anger when senator ron johnson pushed her about statements by u.N. Ambassador susan rice, made on tv, in the days after the attacks. We were misled that there were supposedly protests and something sprang out of that. With all due respect, the fact is, we had four dead americans, was it because of a protest of guys out for a walk one night? What difference at this point, does it make? It is our job to figure out what happened and do everything we can to prevent it from ever happening again, senator. Reporter: Tomorrow, clinton will introduce the man nominated to replace her, john kerry, so, today is likely the last long look the american public will have of hillary clinton for awhile. And, diane, there is no doubt she has left a vivid impression. It was memorable.
This transcript has been automatically generated and may not be 100% accurate.