One of the main features of the internet age is the tendency of politicians to misunderstand the World Wide Web – thinking they can control it, or treating wider social problems as if they had been caused by it.

Now it’s the turn of British Prime Minister David Cameron. He wants to restrict access to pornography, saying he is concerned about the safety of children. I am sure that the vast majority of people are keen to see an end to child abuse. Most of us would back policies likely to reduce it. Sexual violence is widespread in Britain, as recent revelations about the BBC and various churches have reminded us.

But we as a society are deeply hypocritical about sexual violence. Newspapers whip up fear of paedophiles on street corners while ignoring the reality that most child abuse takes place in the home. The ministers who talk about protecting children have cut benefits that help parents to spend time with their children. People who are raped continue to be blamed for the actions of rapists. The last government brought in a law that restricts a great deal of amateur and ‘homemade’ porn while doing nothing to challenge exploitation in the massive corporate pornography industry.

So it’s no surprise that David Cameron’s proposals seem highly unlikely to reduce abuse. At the same time, they may harm young people and others who turn to the internet to find help.

Politicians who try to control internet access are sometimes motivated by a desire to suppress dissent, sometimes by the more laudable aims of preventing child abuse or terrorism. In either case, they rarely succeed.

During the Arab Spring in 2011, Egyptian President Hosni Mubarak tried to close down access to Twitter. It took activists only four hours to get it back. Later that year in London, the acting head of the Metropolitan Police considered shutting Twitter in response to riots. Only after enquiring about it did he discover that he had no authority to do so. In any case, the rioters were communicating mainly on Blackberry Messenger.

It is difficult to believe that any state that gains new powers over internet access will only ever use them to control access to pornography. But even if we accept that this is possible, the policy is not effective on its own terms. Cameron wants to produce a ‘blacklist’ of words and phrases that will be blocked if people search for them. Sadly, child abusers will not take long to work their way around this. It will be almost impossible to keep up with the development of code words. Are our rulers really this naïve about the workings of the internet?

Cameron and his supporters in the media seem not to understand the way in which the internet affects communication. The internet makes things easier. To put it crudely, it makes good things easier and it makes bad things easier. A blacklist would stop entirely legitimate searches about sexual health and sexual ethics. Will gay, lesbian, bisexual, asexual and transgender teenagers no longer be able to visit sites on which they can discuss their struggles and fears? The internet has been a lifeline for many young people struggling with their sexuality. It is a bitter irony that David Cameron has announced this policy less than a week after same-sex marriage was legalized in England and Wales.

David Cameron became somewhat confused when it was pointed out that he has no definition of pornography. To talk about all websites mentioning or depicting sex as if they were the same is an insult to the victims of abuse.

An adult couple who consensually spank each other and upload a video depicting this can hardly be compared to the exploitative corporate pornography industry, let alone to a group of child abusers. Of course, even with ‘homemade’ porn, there are problems with children gaining access to it, but we will not solve these problems by encouraging a general fear of sex, rather than tackling the massive social problems of abuse, misogyny and rape culture.

It is both sad and worrying that the very people who are cheering most loudly for this law – such as the Daily Mail and rightwing Christian groups – are also the first to condemn sex education in primary schools. If we are serious about fighting sexual abuse, we need to empower children through meaningful education on sex and relationships from an early age, helping them to report abuse, to respect their own and each other’s bodies, to understand the practical and moral choices available to them and to help them build respectful and mutually fulfilling relationships as they grow up.

David Cameron, like most people who blame the internet for society’s ills, risks creating the illusion of tackling abuse while reducing young people’s access to information and help. His proposals are worse than useless. They are actively harmful.

Symon Hill is the author of Digital Revolutions: Activism in the Internet Age.