Lee C. Bollinger 
Tolerant Society [PDF ebook] 

Bollinger provides a masterful critique of the major theories of freedom of expression, finding these theories persuasive but inadequate. Buttressing his argument with references to the Skokie case and many other examples, as well as a careful analysis of the primary literature on free speech, he contends that the real value of toleration of extremist speech lies in the extraordinary self-control toward antisocial behavior that it elicits: society is strengthened by the exercise of tolerance.