I'm not certain whether or not the president has the power, but it must be noted as rather ironic that two people that are VERY CLEARLY opposed to the President attacking a country without congressional approval are Obama and Biden....

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"The President does not have power under the Constitution to unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat to the nation. As Commander-in-Chief, the President does have a duty to protect and defend the United States. In instances of self-defense, the President would be within his constitutional authority to act before advising Congress or seeking its consent. History has shown us time and again, however, that military action is most successful when it is authorized and supported by the Legislative branch."
*Senator Barack Obama, 2007*
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And here is Joe Biden, saying that if Bush bombs Iran without congressional approval, he should be impeached.
.C'mon everybody, you have to admit that it's funny!
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