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Now the only civilised response in the modern world to what someone says that you do not like is to reply in kind - that is with words, not actions and certainly not violence. A verbal or written criticism of what someone has said is just as much an exercise of freedom of expression as what is being criticised. There is no right not to criticise, since the whole point of freedom of expression means everyone is open to criticism, without exception. If no-one ever became upset over statements made then there would be no issue of free expression, it only occurs when one disagrees with another and says so. Freedom of expression is not constrained by however sound or valid the arguments are on either side, indeed it is a pre-requisite to finding out the soundness and validity of such arguments. Freedom of expression enables everyone to debate and criticise, direclty or indirectly (say via the internet or youtube videos) on any topic, no topic including religion has a special status in this regard, and we must defend against any existing or attempts to impose any double standards here.
With freedom of expression the defenders of the specific Islamic teachings he was criticising have a freedom of expression to say respond kind. If they don't like Wilder's video, they can exercise their own freedom of expression and make a video response. However do not use the Dutch government as a weapen to censure freedom of expression. Anyone who does or supports such actions desrves to be strongly condemned. Indeed it is exactly those who attempt to use such mechanisms to suppress free speech and their supporters, who need to be specifically criticised for threatening freedom of expression - by exercising our own freedom of expression of course! If they had their own way, this would be impossible and we would start regressing back to the middle ages or worse.
Now with regard to the issue of "hate speech" see this link from the NSS:
So whether you are Muslim or not, for or against religion, if you wish to support the hard won freedoms that enable us all to chose how to live and express ourselves then please sign the petition.
You don’t have to support anything that Geert Wilders stands for in order to defend the principle that he should have the right to say what he wants, so long as he does not incite hatred against people. We must maintain a clear distinction between condemning ideas and condemning those who hold those ideas.