Robert F. Turner, is co-founder of the Center for National Security Law at the University of Virginia School of Law, and served as counsel to the President's Intelligence Oversight Board, 1982-84. He explains why Bush's actions were legal:

    For nearly 200 years it was understood by all three branches that intelligence collection--especially in wartime--was an exclusive presidential prerogative vested in the president by Article II, Section 1 of the Constitution.

    Washington, Madison, Jefferson, Hamilton, John Marshall and many others recognized that the grant of "executive power" to the president included control over intelligence gathering. It was not by chance that there was no provision for congressional oversight of intelligence matters in the National Security Act of 1947.

    the Constitution is the highest law of the land, and when Congress attempts to usurp powers granted to the president, its members betray their oath of office. In certain cases, such as the War Powers Resolution and the Foreign Intelligence Surveillance Act, it might well have crossed that line.

    Keep in mind that while the Carter administration asked Congress to enact the FISA statute in 1978, Attorney General Griffin Bell emphasized that the law "does not take away the power of the president under the Constitution." And in 1994, when the Clinton administration invited Congress to expand FISA to cover physical as well as electronic searches, the associate attorney general testified: "Our seeking legislation in no way should suggest that we do not believe we have inherent authority" under the Constitution. "We do," she concluded.

    In the 1980 Truong case, the Fourth U.S. Circuit Court of Appeals upheld the warrantless surveillance of a foreign power, its agent or collaborators (including U.S. citizens) when the "primary purpose" of the intercepts was for "foreign intelligence" rather than law enforcement purposes. Every court of appeals that has considered the issue has upheld an inherent presidential power to conduct warrantless foreign intelligence searches; and in 2002 the U.S. Foreign Intelligence Surveillance Court of Review, created by the FISA statute, accepted that "the president does have that authority" and noted "FISA could not encroach on the president's constitutional power."

    America is at war with a dangerous enemy. Since 9/11, the president, our intelligence services and our military forces have done a truly extraordinary job--taking the war to our enemies and keeping them from conducting a single attack within this country (so far).

    But we are still very much at risk, and those who seek partisan political advantage by portraying efforts to monitor communications between suspected foreign terrorists and (often unknown) Americans as being akin to Nixon's "enemies lists" are serving neither their party nor their country. The leakers of this sensitive national security activity and their Capitol Hill supporters seem determined to guarantee al Qaeda a secure communications channel into this country so long as they remember to include one sympathetic permanent resident alien not previously identified by NSA or the FBI as a foreign agent on their distribution list.