According to the Supreme Court (ruling in a case in which some people tried to blow up a CIA office in Michigan, and thus very much relevant to the domestic security area of so-called "war on terrorism"), wiretapping for the purpose of national security MOST CERTAINLY DOES require a warrant where U.S. citizens are involved, because the Government's duty to preserve national security DOES NOT override the 4th Amendment rights of U.S. citizens.
Every argument Bush and his supporters have put forward so far in defense of his actions in authorizing wiretaps without warrants in cases where U.S. citizens are on one or both ends of the conversations is refuted by the Court's ruling in this case, which is still the law of the land with regard to warrants for national security-related wiretaps & similar electronic surveillance. One wonders whether the White House Counsel (and ex-Supreme Court nominee) somehow missed this ruling when briefing her boss about what to say to the media in defense of his actions.
Excerpts from United States v. United States District Court, 407 U.S. 297, 302 -08 (1972), sections 2, 3, and 4. Justice Powell, writing the official opinion:
Though the Government and respondents debate their seriousness and magnitude, threats and acts of sabotage against the Government exist in sufficient number to justify investigative powers with respect to them. The covertness and complexity of potential unlawful conduct against the Government and the necessary dependency of many conspirators upon the telephone make electronic surveillance an effective investigatory instrument in certain circumstances. The marked acceleration in technological developments and sophistication in their use have resulted in new techniques for the planning, commission, and concealment of criminal activities. It would be contrary to the public interest for Government to deny to itself the prudent and lawful employment of those very techniques which are employed against the Government and its law-abiding citizens.
It has been said that "[t]he most basic function of any government is to provide for the security of the individual and of his property." Miranda v. Arizona, 384 U.S. 436, 539 (1966) (WHITE, J., dissenting). And unless Government safeguards its own capacity to function and to preserve the security of its people, society itself could become so disordered that all rights and liberties would be endangered. As Chief Justice Hughes reminded us in Cox v. New Hampshire, 312 U.S. 569, 574 (1941):
"Civil liberties, as guaranteed by the Constitution, imply the existence of an organized society maintaining public order without which liberty itself would be lost in the excesses of unrestrained abuses."
But a recognition of these elementary truths does not make the employment by Government of electronic surveillance a welcome development - even when employed with restraint and under judicial supervision. There is, understandably, a deep-seated uneasiness and apprehension that this capability will be used to intrude upon cherished privacy of law-abiding citizens. We look to the Bill of Rights to safeguard this privacy.
National security cases, moreover, often reflect a convergence of First and Fourth Amendment values not present in cases of "ordinary" crime. Though the investigative duty of the executive may be stronger in such cases, so also is there greater jeopardy to constitutionally protected speech. [...] History abundantly documents the tendency of Government - however benevolent and benign its motives - to view with suspicion those who most fervently dispute its policies. Fourth Amendment protections become the more necessary when the targets of official surveillance may be those suspected of unorthodoxy in their political beliefs. The danger to political dissent is acute where the Government attempts to act under so vague a concept as the power to protect "domestic security."
The price of lawful public dissent must not be a dread of subjection to an unchecked surveillance power. Nor must the fear of unauthorized official eavesdropping deter vigorous citizen dissent and discussion of Government action in private conversation. For private dissent, no less than open public discourse, is essential to our free society.
As the Fourth Amendment is not absolute in its terms, our task is to examine and balance the basic values at stake in this case: the duty of Government to protect the domestic security, and the potential danger posed by unreasonable surveillance to individual privacy and free expression. If the legitimate need of Government to safeguard domestic security requires the use of electronic surveillance, the question is whether the needs of citizens for privacy and free expression may not be better protected by requiring a warrant before such surveillance is undertaken. We must also ask whether a warrant requirement would unduly frustrate the efforts of Government to protect itself from acts of subversion and overthrow directed against it.
These Fourth Amendment freedoms cannot properly be guaranteed if domestic security surveillances may be conducted solely within the discretion of the Executive Branch. The Fourth Amendment does not contemplate the executive officers of Government as neutral and disinterested magistrates. Their duty and responsibility are to enforce the laws, to investigate, and to prosecute. Katz v. United States, supra, at 359-360 (DOUGLAS, J., concurring). But those charged with this investigative and prosecutorial duty should not be the sole judges of when to utilize constitutionally sensitive means in pursuing their tasks. The historical judgment, which the Fourth Amendment accepts, is that unreviewed executive discretion may yield too readily to pressures to obtain incriminating evidence and overlook potential invasions of privacy and protected speech.
These contentions in behalf of a complete exemption from the warrant requirement, when urged on behalf of the President and the national security in its domestic implications, merit the most careful consideration. We certainly do not reject them lightly, especially at a time of worldwide ferment and when civil disorders in this country are more prevalent than in the less turbulent periods of our history. There is, no doubt, pragmatic force to the Government's position.
But we do not think a case has been made for the requested departure from Fourth Amendment standards. The circumstances described do not justify complete exemption of domestic security surveillance from prior judicial scrutiny. Official surveillance, whether its purpose be criminal investigation or ongoing intelligence gathering, risks infringement of constitutionally protected privacy of speech. Security surveillances are especially sensitive because of the inherent vagueness of the domestic security concept, the necessarily broad and continuing nature of intelligence gathering, and the temptation to utilize such surveillances to oversee political dissent. We recognize, as we have before, the constitutional basis of the President's domestic security role, but we think it must be exercised in a manner compatible with the Fourth Amendment. In this case we hold that this requires an appropriate prior warrant procedure.
Nor do we believe prior judicial approval will fracture the secrecy essential to official intelligence gathering. The investigation of criminal activity has long involved imparting sensitive information to judicial officers who have respected the confidentialities involved. Judges may be counted upon to be especially conscious of security requirements in national security cases. Title III of the Omnibus Crime Control and Safe Streets Act already has imposed this responsibility on the judiciary in connection with such crimes as espionage, sabotage, and treason, 2516 (1) (a) and (c), each of which may involve domestic as well as foreign security threats. Moreover, a warrant application involves no public or adversary proceedings: it is an ex parte request before a magistrate or judge. Whatever security dangers clerical and secretarial personnel may pose can be minimized by proper administrative measures, possibly to the point of allowing the Government itself to provide the necessary clerical assistance.
Thus, we conclude that the Government's concerns do not justify departure in this case from the customary Fourth Amendment requirement of judicial approval prior to initiation of a search or surveillance. Although some added burden will be imposed upon the Attorney General, this inconvenience is justified in a free society to protect constitutional values. Nor do we think the Government's domestic surveillance powers will be impaired to any significant degree. A prior warrant establishes presumptive validity of the surveillance and will minimize the burden of justification in post-surveillance judicial review. By no means of least importance will be the reassurance of the public generally that indiscriminate wiretapping and bugging of law-abiding citizens cannot occur.
Also worth reading is the FindLaw annotation of the Fourth Amendment regarding the concept of warrantless national security electronic surveillance. Although it mostly just summarizes the above excerpts, it is written in plainer speech.
Feudalism: Serf & Turf