Loss of liberty and privacy, if legally sanctioned and absolutely necessary (and this is a huge and unfulfilled "if"), should at least result in some good. A serious problem with massive, untargeted and illegal wiretaps (and perhaps with future government-mandated Google searches or even informal Amazon ones -- link: http://www.applefritter.com/bannedbooks), however, is that they'd likely be ineffective. The volume of the information generated by them would make it essentially impossible to follow up on the "leads" generated. There isn't the manpower to investigate more than a tiny fraction of them in real time.
Yet another problem is the perennial problem of false positives (about which I wrote here when the Total Information Awareness program was being considered). Even if an accurate profile of potential terrorists is drawn, the fact that such a vanishingly small percentage of us are terrorists means that the vast majority of the people investigated will be innocent.
Even if the probability that the purported terrorist profile is accurate were an astonishing 99 percent (if someone has terrorist ties, the profile will pick him or her out 99 percent of the time, and, for ease of computation, if someone does not have such ties, the profile will pick him or her out only 1 percent of the time), most of the hits would be false positives.
For illustration, let's further assume that one out of a million American residents has terrorist ties -- that's approximately 300 people -- and the profile will pick out 99 percent, or 297 of them. Great. But what of the approximately 300 million innocent Americans? The profile will also pick out 1 percent of them, "only" 3 million false positives, innocent people who will be caught up in a Kafkaesque dragnet.
It should be reiterated that such broad scale wiretapping and data mining is not only of questionable legality if not downright unconstitutional, but it is also ineffective and a waste of resources. Terrorism is a problem, but so are handguns, health care, the deficit, the environment, education, and a host of other issues that are more important to our personal and, I think, our national security.
There are legal means to fight terrorists and limit children's (but not adults') access to porn that don't require that we sacrifice our constitutional freedoms and privacy rights. If I may make another local reference, recall that Philadelphian Benjamin Franklin, whose 300th birthday celebration just passed, famously wrote: "Those who would sacrifice liberty for security deserve neither." What they might deserve is the surveillance state toward which we seem to be heading.
Professor of mathematics at Temple University, John Allen Paulos is the author of best-selling books including "Innumeracy" and "A Mathematician Plays the Stock Market." His "Who's Counting?" column on ABCNews.com appears the first weekend of every month.