Holder cited the attacks at Pearl Harbor and on Sept. 11, 2001, as examples.

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He reminded the cadets the surprise attack by Japan on Pearl Harbor in 1941 sparked dramatic changes in the military and the September 11 attacks have done the same.

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Holder said a potential scenario might involve a president ordering such action "to protect the homeland" in a case like the 2001 al Qaeda attacks on New York and Washington or the Japanese bombing of Pearl Harbor in 1941.

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