Mr. Thomas Sowell makes a number of utterly invalid, but unfortunately typical, arguments in favor of the USA PATRIOT act.[1] Most tellingly, and perhaps most compellingly, he compares the Patriot act to the polio vaccine, and to the Cold War. He is correct, people sheltered from polio by vaccination did, historically come to question the need for that vaccine. And that did cause a temporary return of the disease until the use of the vaccine picked back up. And Europe and the left here do typically fail to understand the role that The United State's military might played in preventing the deployment of our armed forces.
However, it is utterly invalid to use these examples to justify the Patriot act. The logic here is p prevents q, r prevents s, therefor t prevents u. No proof is offered that the relationship between p and q, r and s, or t and u is the same. A "justification" such as this could, then, be used to assert that literally anything was necessary. You could just as easily say that the reason for no new terrorist activity was because people are flying less! Sadly, this failure of logic will escape many people.
Similarly, he tries to pull of a nice switch. The Patriot act is supposedly responsible for the fact that no second attack on the scale of the World Trade Center collapse has taken place. Thus its use to disrupt and crack down on domestic terrorists has been successful and responsible for that lack. Notice the switch there? The World Trade Center did not fall because of domestic terrorists. Rather, it fell because of international ones. So the use of the Patriot act against domestic terrorists has no necessary (it might have an incidental) causal relationship with the lack of a similar attack.
Someday perhaps I will see a valid argument for the USA PATRIOT Act. Until then I will persist in believing that its costs are far greater than its benefits.
[1] http://www.townhall.com/columnists/thomassowell/ts20050616.shtml