On April 1, 2011, a quite appropriate date for what follows, the Office of Legal Counsel (OLC), the office in the Justice Department which is supposed to supply advice to the Executive branch on whether what it is doing is legal, opined that
the President has the power to commit United States troops abroad," as well as to "take military action," "for the purpose of protecting important national interests," even without specific prior authorization from Congress.
and
Moreover, the President as Commander in Chief "superintend[s] the military,"Loving v. United States, 517 U.S. 748, 772 (1996), and "is authorized to direct the movements of the naval and military forces placed by law at his command."
The OLC, of course, is the same office from which John Yoo wrote his famous memos legitimizing torture and advancing the theory that the President had unlimited powers in war. The war Yoo had in mind was the war on terror, and, as that essentially had no end, the dictatorial power he sought for the President was effectively permanent...