I assume Vonnegut is referring to claims that under the Patriot Act, John Ashcroft's goons have been terrorizing libraries and monitoring Americans' reading habits. In fact, law enforcement agencies have always had the power to request library records as part of a criminal investigation; a provision of the Patriot Act gave them the power to do so in counterterrorism investigations without notifying the suspect. (Remember, we're talking about materials related to terrorist acts and not, say, the wit and wisdom of Michael Moore.) Whether or not such powers are appropriate, in the two years after the passage of the Patriot Act this provision was used exactly ... zero times. [Young's ellipses.]
In the year after the World Trade Center and Pentagon attacks, Federal and local law enforcement officials visited at least 545 (10.7%) libraries to ask for these records. Of these, 178 libraries (3.5%) received visits from the FBI. The number of libraries queried fell significantly below the 703 libraries reporting such requests the year before the terrorist events. The actual number questioned in the past year may, however, be larger, because the USA Patriot Act makes it illegal for persons or institutions to disclose that a search warrant has been served. A warning about these secrecy provisions on the LRC questionnaire may have served, in some cases, as a deterrent to candid answers. Fifteen libraries acknowledged there were questions they did not answer because they were legally prohibited from doing so.
In other words, the answer to the question of whether and how the Patriot Act is being used to snoop on library patrons is inherently unknowable, since the act also makes it a crime for librarians to disclose whether they've been visited or not. The very fact that the number of reported library visits by law-enforcement officials fell in the year after 9/11 is telling, wouldn't you say?