The freedom of speech can be curtailed when it represents a serious threat to society  Freedom of speech certainly may be curtailed when real harms can be shown to arise from it. Extremist sites serve as centers of dangerous dissent, whose members threaten all of society. They promote a message that is fundamentally bad speech, because it cannot it cannot be argued with and promotes aims that are so anathema to free society that its dissemination represents a true threat to people’s safety. The threat extremists represent to free society demands that their right to speech online be curtailed. [1] By blocking these sites, ISPs certainly are denying some freedom of speech, but it is a necessarily harmful form of speech that has no value in the global commons. Thus, there is essentially no real loss of valuable speech in censoring extremist websites.  [1] Kaplan, E. “Terrorists and the Internet”. Council on Foreign Relations. 8 January 2009.