Walter Berns of the American Enterprise Institute has written an Opinion piece in the Wall Street Journal entitled "Interrogations and Presidential Prerogative" (Saturday, May 23, 2009, see here) and subtitled "The Founders created an executive with substantial discretionary powers." The piece is well worth the reading. I quote from it here. The italics are in the original article, but the bold face is mine:
But Locke admitted that not everything can be done by law. Or, as he said, there are many things "which the law can by no means provide for." The law cannot "foresee" events, for example, nor can it act with dispatch or with the appropriate subtlety required when dealing with foreign powers. Nor, as we know very well indeed, can a legislative body preserve secrecy.
Such matters, Locke continued in the Second Treatise, should be left to "the discretion of him who has the executive power." It is in this context that he first spoke of the "prerogative": the "power to act according to discretion, for the public good without the prescription of the law, and sometimes even against it." He concluded by saying "prerogative is nothing but the power of doing public good without a rule" (italics in the original).
Many may be uncomfortable with Locke's thinking or with the fact that the Constitution's Article II establishes a executive that consists of a single human being empowered with the role of Commander in Chief of the Army and Navy. However, that is what our Constitution has done. Thank God for it.