businesses and people need privacy
1). This is being pushed by MarkMonitor, a lobbying group behind SOPA that represents copyright extremists like the RIAA and MPAA. They want to figure out the hosts of websites that have infringing content. But they already have plenty of recourse to find out that information through a judicial review, they just want to be able to take down websites faster without having to go through the pesky legal processes of proving that in court. It lacks due process. 2). Websites aren't strictly commercial. This essentially allows for doxxing of people who have not only the right but the NEED to be anonymous online. Think about the physical danger the owner of a controversial website like Planned Parenthood would be in if forced to reveal such details as their home address. 3). In countries that try to restrict free speech, think about how easy it would be to go after journalists and whistleblowers who rely on the anonymity of the internet to get their information out there to a public that has a right to know.