Obama Announces Chuck Hagel for Secretary of Defense washington, where the president today announced his new team for a new term. Today, it was national security. He nominated former senator chuck hagel for secretary of defense. Hagel, a man who volunteers for vietnam, who was awarded two purple hearts for his courage. But tonight, he is already facing political fire. Abc's chief global affairs correspondent martha raddatz tells us. Reporter: President obama made clear today just how important this nomination is for the country. My most solemn obligation is the security of the american people. Reporter: Through decades of war and peace, the defense secretary job has than profound implications. If forces to be used, saddam hussein would be removed from power. Reporter: Chuck hagel knows the horrors of war first hand. At 21, a poor kid from nebraska, he volunteered to go to vietnam, fighting side-by-side with his 19-year-old brother, tom. He got two purple hearts. One, when shrapnel ripped open his chest. Another, a month later, when hagel himself on fire from a land mine rescued his brother. I was on the left side, where major blast came up and I was burned all up and down the left side of my body. So, I grabbed tom out, he was out and he had blood coming out of his ears and nose. And you don't have time to think about, is he dead or alive? Reporter: But critics are not focusing on hagel's military service. While serving as a republican senator, he angered some in his own party for not backing the troop surge in iraq. Not supporting unilateral sanctions against iran. And what some on the hill perceive as a lack of support for israel. Hagel's record is very, very troubling on the nation of israel. He has not been a friend to israel. Reporter: Hagel and the white house say these are misperceptions. With hagel telling his hometown paper today he has unequivocal, total support for israel. But he still has a lot of convincing to do on capitol hill. His confirmation is far from guaranteed and the chorus against his nomination seems to be getting louder, despite the best efforts of the white house. All right, thank you so much, martha. And as you know, the president's other big pick today was for the man he wants to lead the cia. His white house terrorism adviser, john brennan, whose work ethic is legend. In fact, the president hailed him for standing watch over the nation and teased him about it. In the summer, august, he's in full suit and tie and one of the reporters asked him, don't you ever get any down time? And john said, "i don't do down time." He's not even smiling now.