Federal law enforcement has legitimate concerns and obligations. The Internet can be a very anonymous society, and as a result, has also become a place for criminals of all stripes to hide their activities. These include political extremists like neo Nazis and Skin Heads who organize and recruit members in order to disseminate their views and activities all buried under the guise of innocuous mail and conversation. We know that recipes for bombs can be found, computer viruses freely distributed and that fringe groups functioning on the edge of the law advocating sedition have operated with impunity until quite recently. It is also of note that one must first be intent upon finding such information.
Ordinary business is present and growing.
While perceived as beneficial by many, it is damned by others. Think of any commercial enterprise and it can be found on the Internet. This presence has also attracted shady elements which have traditionally profited on the fringes or illegally at the expense of legitimate business. After all, with the possible exception of software, you really can't see, touch or smell what you are buying. Additionally, our computer systems are vulnerable to those who choose to profit from our private information.