Don Wood at Library 2.0 has a good, short post on Why Privacy and Confidentiality Are Important.

He notes that "For libraries to flourish as centers for uninhibited access to information, librarians must stand behind their users' right to privacy and freedom of inquiry."

If libraries do not have copies of digital government information, users will be faced with retrieving that information from government-controlled web servers where there is no guarantee of privacy (Will GPO guarantee user privacy? Can it?). If libraries want to flourish as centers of uninhibited access to information, they need to have copies of digital government information.