Hagel confirmed as U.S. defense secretary

WASHINGTON -- Chuck Hagel's rocky and inauspicious path to leadership of the Pentagon could haunt him if he doesn't watch his step.

"If people feel Hagel makes a mistake in the future, they will come after him even harder than if this ugly process of recent weeks hadn't happened," said Michael O'Hanlon, a senior fellow at the Brookings Institution and a co-author of "Bending History: Barack Obama's Foreign Policy."

Chuck Hagel Fast Facts:

Hagel's nomination as defense secretary was subject to harsh criticism from some Republicans over past statements on sensitive political and national security matters.

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