There will always be some limits to freedom of speech or expression. Try shouting “fire” in a crowded theater. Some of those limits can be seen in laws across the world and they cover “hate speech.” There are also laws about discrimination.

Websites and social media are not immune from action being taken. The defense that would be used on this site is that content is user-generated, but this may not absolve the owners of some responsibility.

Facebook has been criticized recently for anti-Semitic practices in allowing advertisers to focus on people who search for topics like, “Jew Hater” or “ How to Burn Jews”. Then there’s the Russian group promoting racist, anti-immigrant and homophobic political messages. Several hate-groups, including white supremacists and neo-Nazis have also been given space on Facebook.

Now there will be some, like another poster here on this topic, who believe it's all just a matter of degree and really 'X is a decent human being'. The logic goes something like this: Pol Pot was a mass murderer but he's better that Joe Stalin as Joe killed more people.