Chuck Hagel was sworn in as Defense Secretary today shortly after arriving to the Pentagon for his first day on the job.

Hagel arrived at the Pentagon this morning 40 minutes late after being caught in Washington D.C'.'s morning rush hour traffic. As Hagel's SUV pulled up to the Pentagon's River Entrance, Marine Lt. Gen. Thomas Waldhauser walked up to the car's door and greeted Hagel with a crisp salute.

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Hagel appeared surprised by the greeting and with a smile quickly saluted back. Waldhauser will serve as Hagel's military aide, the same job he did for former Defense Secretary Leon Panetta.

Hagel and his wife Lillibet walked up the stairs into the building and turned to say "good morning" to the reporters and camera crews on hand to record his arrival.

A short time later, Hagel was sworn in as Defense Secretary in a small private ceremony at 8:30 a.m. private ceremony inside his new offices.

Hagel was sworn in by the Pentagon's Director of Administration and Management Michael L. Rhodes.

With all the drama of his confirmation past him, Hagel will now get down to doing the work of a Defense Secretary.

After his swearing-in he presided over the regular daily staff meeting and will speak to Pentagon staffers at a morning event later Wednesday.

He will continue with other meetings before heading to the White House for scheduled meetings there.