If I understand the judge correctly, he says that the program may well be illegal if it violages FISA, but that the important issue is whether it is effective and necessary.
Lawyers who are busily debating legality without first trying to assess the consequences of the program have put the cart before the horse. Law in the United States is not a Platonic abstraction but a flexible tool of social policy. In analyzing all but the simplest legal questions, one is well advised to begin by asking what social policies are at stake. Suppose the NSA program is vital to the nation's defense, and its impingements on civil liberties are slight. That would not prove the program's legality, because not every good thing is legal; law and policy are not perfectly aligned. But a conviction that the program had great merit would shape and hone the legal inquiry. We would search harder for grounds to affirm its legality, and, if our search were to fail, at least we would know how to change the law--or how to change the program to make it comply with the law--without destroying its effectiveness. Similarly, if the program's contribution to national security were negligible--as we learn, also from the Times, that some FBI personnel are indiscreetly whispering--and it is undermining our civil liberties, this would push the legal analysis in the opposite direction.
The next terrorist attack (if there is one) will likely be mounted, as the last one was, from within the United States but orchestrated by leaders safely ensconced abroad. So suppose the NSA learns the phone number of a suspected terrorist in a foreign country. If the NSA just wants to listen to his calls to others abroad, FISAdoesn't require a warrant. But it does if either (a) one party to the call is in the United States and the interception takes place here or (b) the party on the U.S. side of the conversation is a "U.S person"--primarily either a citizen or a permanent resident. If both parties are in the United States, no warrant can be issued; interception is prohibited. The problem with FISA is that, in order to get a warrant, the government must have grounds to believe the "U.S. person" it wishes to monitor is a foreign spy or a terrorist. Even if a person is here on a student or tourist visa, or on no visa, the government can't get a warrant to find out whether he is a terrorist; it must already have a reason to believe he is one....
As far as an outsider can tell, the NSA program is designed to fill these gaps by conducting warrantless interceptions of communications in which one party is in the United States (whether or not he is a "U.S. person") and the other party is abroad and suspected of being a terrorist. But there may be more to the program. Once a phone number in the United States was discovered to have been called by a terrorist suspect abroad, the NSA would probably want to conduct a computer search of all international calls to and from that local number for suspicious patterns or content. A computer search does not invade privacy or violate FISA, because a computer program is not a sentient being. But, if the program picked out a conversation that seemed likely to have intelligence value and an intelligence officer wanted to scrutinize it, he would come up against FISA's limitations. One can imagine an even broader surveillance program, in which all electronic communications were scanned by computers for suspicious messages that would then be scrutinized by an intelligence officer, but, again, he would be operating outside the framework created by FISA.
FISA's limitations are borrowed from law enforcement. When crimes are committed, there are usually suspects, and electronic surveillance can be used to nail them. In counterterrorist intelligence, you don't know whom to suspect--you need surveillance to find out. The recent leaks from within the FBI, expressing skepticism about the NSA program, reflect the FBI's continuing inability to internalize intelligence values. Criminal investigations are narrowly focused and usually fruitful. Intelligence is a search for the needle in the haystack. FBI agents don't like being asked to chase down clues gleaned from the NSA's interceptions, because 99 out of 100 (maybe even a higher percentage) turn out to lead nowhere. The agents think there are better uses of their time. Maybe so. But maybe we simply don't have enough intelligence officers working on domestic threats.
What seems clear is that FISA does not provide an adequate framework for counterterrorist intelligence. The statute was enacted in 1978, when apocalyptic terrorists scrambling to obtain weapons of mass destruction were not on the horizon. From a national security standpoint, the statute might as well have been enacted in 1878 to regulate the interception of telegrams. In the words of General Michael Hayden, director of NSA on September 11 and now the principal deputy director of national intelligence, the NSA program is designed to "detect and prevent," whereas FISA was built for long-term coverage against known agents of an enemy power."
In the immediate aftermath of the September 11 attacks, Hayden, on his own initiative, expanded electronic surveillance by NSA without seeking FISA warrants. The United States had been invaded. There was fear of follow-up attacks by terrorists who might already be in the country. Hayden's initiative was within his military authority. But, if a provision of Fthat allows electronic surveillance without a warrant for up to 15 days following a declaration of war is taken literally (and I am not opining on whether it should or shouldn't be; I am not offering any legal opinions), Hayden was supposed to wait at least until September 14 to begin warrantless surveillance. That was the date on which Congress promulgated the Authorization for Use of Military Force, which the administration considers a declaration of war against Al Qaeda. Yet the need for such surveillance was at its most acute on September 11. And, if a war is raging inside the United States on the sixteenth day after an invasion begins and it is a matter of military necessity to continue warrantless interceptions of enemy communications with people in the United States, would anyone think the 15-day rule prohibitive?
We must not ignore the costs to liberty and privacy of intercepting phone calls and other electronic communications. No one wants strangers eavesdropping on his personal conversations. And wiretapping programs have been abused in the past. But, since the principal fear most people have of eavesdropping is what the government might do with the information, maybe we can have our cake and eat it, too: Permit surveillance intended to detect and prevent terrorist activity but flatly forbid the use of information gleaned by such surveillance for any purpose other than to protect national security. So, if the government discovered, in the course of surveillance, that an American was not a terrorist but was evading income tax, it could not use the discovery to prosecute him for tax evasion or sue him for back taxes. No such rule currently exists. But such a rule (if honored) would make more sense than requiring warrants for electronic surveillance.
Once you grant the legitimacy of surveillance aimed at detection rather than at gathering evidence of guilt, requiring a warrant to conduct it would be like requiring a warrant to ask people questions or to install surveillance cameras on city streets. Warrants are for situations where the police should not be allowed to do something (like search one's home) without particularized grounds for believing that there is illegal activity going on. That is too high a standard for surveillance designed to learn rather than to prove.
Posner makes some good points, particularly about the dubiousness of the FBI's complaints about leads that go nowhere. But as some of the commenters on the TNR site pointed out, his argument begs the question: if the law is so inadquate to current needs, then why not actually change the law? I really don't buy the idea that this would somehow tip the terrorists off to what we're doing (Al Qaeda operatives would have to be pretty dumb to think they at least may be under surveillance, and I suspect they don't have much confidence in American intelligence agencies' strict abidance by the law).
Secondly -- and knowledgeable people are welcome to correct me on this -- I'm not at all sure that intelligence works the way Posner thinks it does: i.e., that it's a random search for a needle in the haystack rather than the pursuit of some actual leads (e.g. observed behavior that leads to suspicion). Posner seems to be offering a prescription for extremely vast and comprehensive surveillance for the purpose of preventing terrorist acts -- basically the electronic equivalent of living under the constant gaze of surveillance cameras not only in the streets but in our homes. I'm also not sure that the only fear people have is surveillance data being legally used against them. There is also the risk of such data being misused by unscrupulous NSA employees, for instance, or even being used for voyeurism. In his October 7, 2001 New York Times magazine article, "A Watchful State," about the use of surveillance cameras in public places in England, Jeffrey Rosen reports that bored operators in the surveillance program routinely amuse themselves by spying on amorous couples in parked cars.
I do think that Posner raises some legitimate issues about the unique problems posed by terrorism in combination with modern technology. One common argument that I don't find persuasive is that if current rules were enough to get us through the Cold War when our adversary was an armed-to-the-teeth nuclear superpower, they're enough to get us through the War on Terror. But there is, in fact, a unique danger in facing a stateless, amorphous opponent undeterred (unlike the Soviet Union) by the threat of retaliation, and with bases in multiple countries including right here in the U.S. Our enemy today is much more flexible than during the Cold War, and it stands to reason that our response needs to be more flexible, too.
At the same time, surely I cannot be the only person troubled by Posner's proclamation that U.S. law is "not a Platonic abstraction but a flexible tool of social policy." If a liberal were to make such a statement in justifying (for instance) a broader application of the Commerce Clause to promote various social causes, conservatives would howl in outrage. Of course the law is not a Platonic abstraction, but make it too flexible, and you will end up with something like an old Russian proverb translateable roughly as, "The law is like a pole: whichever way you twist it, that's where it will go." In America, we are supposed to live under the rule of law, not merely of social policy.