Some excerpts from Libertarianism: What Everyone Needs to Know.
On the dangers of restricting “offensive speech”.
In a free society, everyone has the right to offend others. A society in which no one has the right to offend others is itself offensive. Libertarians add: Giving everyone a right never to be offended might seem like a recipe for good community and fellow-feeling. No so. It makes each person’s sense of indignation a weapon.
For a contrary view, see here.
On the consequences of free speech:
[…]whether you have the right to say something doesn’t depend on whether society benefits on net from you saying it.
Still, many libertarians believe part of what justifies extensive rights to free speech is that respecting such rights generates good consequences. For instance, John Stuart Mill argues that if you want good consequences—such scientific progress, advancement in the arts, cultural progress, peace, and feelings of mutual respect—then you need to allow free speech regardless of the consequences. This may sound paradoxical. However, Mill says, the policy of only allowing beneficial speech has no history of being beneficial. The policy of only allowing speech that society has judged to be in its best interests has no history of being in society’s best interests
On whether the license to say what one likes undermines community:
Libertarians think that attempting to enforce prudence, virtue, or community through government tends to fail. For example, if a religious community persists only by forbidding disagreement, the community is a sham.
Conservatives and left-liberals alike take this to show that libertarians have no community spirit. Libertarians find this puzzling. They ask, why would “caring about community” involve pushing others around or subjugating them to the group’s will? Conservatives and left-liberals alike often think we must use violence to encourage community, perhaps by outlawing certain ideas or lifestyles or by forcing citizens to do community service or vote. […]Libertarians say, if a community can flourish only in an atmosphere of oppression, then that community is no real community at all. Truly loving communities—just like loving families—do not need these kind of background threats to survive.
I didn’t dedicate much space to free speech issues, in part because most readers* will tend to favor an extensive right of free speech. However, had I read Waldron’s book before writing this, I might have added a paragraph arguing with him.
*Or at least most American readers. I just learned the book will be translated into Mongolian and re-published by Nepko Publishing. I know very little about Mongolian political dispositions.