Better To Know Who The Bigots Are
Greg Lukianoff, of campus free speech-defending FIRE (Foundation for Individual Rights in Education), writes at CNET of the damage that will be done by purging mass media of hurtful opinions:

"Hate speech" is constitutionally protected in the United States. But the push against "hurtful" and "blasphemous" speech (primarily speech offensive to Islam) is gaining ground throughout the world. Last fall, for example, when many thought a YouTube video that satirized Mohammed caused a spontaneous attack on our consulate in Benghazi, academics across the country rushed to chide America for its expansive protections of speech. And as someone who has spent more than a decade fighting censorship on American college campuses, I run into antagonism toward free speech on a regular basis, most recently last month, when I spoke at Columbia Law School. After my speech, law professor Frederick Schauer criticized his American colleagues for not being more skeptical about the principle of free speech itself.

This has become a fairly standard refrain, in my experience, as academics who want to limit free speech often paint themselves as a beleaguered, enlightened minority struggling against the unquestioned dogma of free speech. Free speech is certainly alive in U.S. courts. For example, since 1989 more than a dozen courts have declared different politically correct college speech codes unconstitutional. Nevertheless, the idea that hurtful or offensive speech should be banned prevails on American campuses: approximately 63 percent of over 400 top colleges maintain codes (PDF) that violate First Amendment principles. Meanwhile, prominent professors, such as Jeremy Waldron and Richard Delgado, attempt to seize the moral high ground for "enlightened censorship," and some students even paint themselves as heroes for tearing down campus "free speech walls."

...Simply making bigoted speech illegal results in two distortions of reality. First, it can create an overly rosy picture of public sentiment, thus preventing real and festering social problems from being addressed. Or second, paradoxically, it may lead people to believe that they live in a far less tolerant society than they actually do.

...The only lasting fix to the real problem of racism or anti-Semitism is cultural. A necessarily incomplete attempt to suppress bigotry may well have far worse unintended consequences, as legal regimes that try to ban hate speech drive social resentments underground, thus preventing the right allocation of resources to address social problems openly.

Twitter lets us see people as they are -- a mixed lot on any given day, to be sure. But it is especially important for a free society to learn not just the good news but the bad news as well.