There is no way that existing copyright law can even remotely be stretched to say that incidental linking to a site on the web constitutes copyright infringemen

There is no way that existing copyright law can even remotely be stretched to say that incidental linking to a site on the web constitutes copyright infringement. This would be akin to saying that a library's use of the Dewey decimal system to help you locate a book infringes the copyright held by the book's owner because it directs you where to find it. The judge's proposal is purely a political one and that is why it appears in a blog. Unless Congress acts to do a radical extension of current copyright law, linking of any normal type will not come under legal scrutiny of any sort, even from Judge Posner (who, whatever else he is, is nobody's fool). The danger here will lie with politicians who might succumb to lobbying pressure. It will not come from judges.