Preventing "objectionable material" from reaching certain audiences does not require government censorship. It could easily be done in a two stage solution:
(1) Web site owners would be required to identify their content in their metatags.
(2) Browsers would by default block content based on said metatags, and users would have to actively choose to turn off the blocks.
Those who see "objectional material" would have to actively enable their browser to do it and seek it out. It would be impossible to "see it by accident". Granted, that might mean people would be forced to verify their age to download or unlock such content, which is annoying. But it would not censor websites nor would it prevent users from seeing content they wish to see.
Cameron's internet filter goes far beyond porn - and that was always the plan
But this was never the case. As Wired reported back in July, Cameron’s ambitions extended far beyond porn. Working through secretive negotiations with ISPs, the coalition has put in place a set of filters and restrictions as ambitious as anything this side of China, dividing the internet into 'acceptable' and 'unacceptable' categories, and cutting people off from huge swathes of it at the stroke of a key.
"As well as pornography, users may automatically be opted in to blocks on "violent material", "extremist related content", "anorexia and eating disorder websites" and "suicide related websites", "alcohol" and "smoking". But the list doesn't stop there. It even extends to blocking "web forums" and "esoteric material", whatever that is. "Web blocking circumvention tools" is also included, of course."
And the restrictions go further still. Over the weekend, people were appalled to discover that BT filters supported homophobia, with a category blocking, "sites where the main purpose is to provide information on subjects such as respect for a partner, abortion, gay and lesbian lifestyle, contraceptive, sexually transmitted diseases and pregnancy."