Legal scholars have spent many a day arguing over whether the President is right or not but they are, with a few exceptions, opposed and appalled by the administration's contempt for any law that restricts their ability to act. Much of the administration's legal arguments have been formulated by a conservative lawyer who, until recently, remained unknown by those outside the legal sphere; John Yoo.
Yoo's work for the administration has received much publicity in light of the President's recent assertion that the Iraq Resolution signed by Congress gave him power to ignore the Fourth Amendment and turn the U.S.'s powerful intelligence apparatus inward.
An interesting history and analysis of the President's role and responsibility regarding international law and the strictures of war powers is up on the New York Review of Books. Georgetown law professor David Cole presents an interesting synopsis of the pertinent law and gives his analysis of the situation.
Cole has publicly come out against the administration's legal positions, but his recount of the history and where the President stands in relation to the framers of the Constitution and established law is important.