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In the US Air Force, there are fewer than 100 active members of the special-operations security force known as DAGRE, or Deployed Aircraft Ground Response Element.
Chief video correspondent Graham Flanagan got an inside look at what it's like on the first day for new freshmen, known as knobs, at the Citadel in Charleston, South Carolina.
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US Navy photo by Mass Communication Specialist 2nd Class Jacob Vernier
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