But Cameron is just doing this because the Daily Mail have whipped up such a storm. He even credits them with being responsible for this issue...

‘The Daily Mail has campaigned hard to make internet search engine filters “default on”. Today they can declare that campaign a success,’ Mr Cameron said.

Source taken from a bizarrely self-congratualtory DM article: http://www.dailymail.co.uk/news/article-2372833/Net-porn-blo...