Communications Minister Senator Stephen Conroy's announcement last week that the Government would legislate a mandatory service provider-level internet filter has galvanised opposition.

The opponents are a loose coalition of many individuals and a range organisations with vaguely common interests, including IT industry and anti-censorship groups, progressive lobby GetUp!, the Pirate Party and the Australian Sex Party.

These groups have been - and continue to be - ineffective because, unlike those who favour the filter, they don't understand what it takes to achieve political change.

Since the Rudd Government came into power with an internet filtering policy, opponents have tried to sway the Government and the public against the filter using the two standard tech-geek argument techniques: logic and sarcasm.

Network engineer Mark Newton has consistently and thoroughly stripped the Government's arguments down to their logical flaws, for example in this recent article on New Matilda.

Jonathan Crossfield's 'open letter to Senator Stephen Conroy from a concerned parent' is a devastating deployment of finely crafted sarcasm.

However, politicians are completely unaffected by sarcasm, having developed immunity through countless hours of exposure during Question Time.

And some would argue they have a similar resistance to logic, or at least that they view rhetorical argument as a pliable tool to be used on either side of any proposition, regardless of truth or merit.

These arguments have also failed to convince the public because the anti-filter groups have allowed their opponents to set the terms and language of the debate.

Senator Conroy has consistently framed the filter in terms of protecting children from online nasties such as child pornography. The mainstream media has almost without exception taken this line uncritically when reporting on the filter.

Politicians don't get logic or sarcasm; they only understand two very different things: money and votes.

Not just any votes, either. Even if GetUp! achieved its goal of 120,000 petition signatures or hundreds of thousands rallied in the streets, the Government might still not be convinced.

To shift position, a politician needs to see significant blocs of people in specific, relevant electorates who would otherwise have voted for his or her party but now intend to vote for the other guys.

This is where the anti-filter movement is failing.

According to Crikey's Pollytics blog, introducing the internet filter would have almost no electoral consequences for the Government, save the possibility of losing inner-city Sydney and Melbourne seats to the Greens.

But not introducing the filter would upset one of the best organised and most influential political groups in the country.

Liberal MP Alex Hawke, a campaigner for Christian values who opposes the filter, believes the legislation is the result of a backroom deal between Senator Conroy and the Australian Christian Lobby (ACL).

The ACL is a seriously hefty lobby group, and the Government owes it favours. According to its website, the ACL counts among its victories "[turning] the tide on issues such as euthanasia" and "[alerting] parliamentarians on industry plans to introduce R-rated hand held computer games".

The ACL has also "positively influenced the debate on homosexual adoption in the ACT and Tasmania" and lobbied local councils on issues such as "the placement of brothels [and] offensive advertising".

Within Parliament, the ACL tells us there are "large numbers of Christian politicians at all levels of Government who value your prayers and support".

You could count on one hand the number of politicians whose knowledge of technology extends further than using a BlackBerry to Tweet during Question Time.

As a result, it is not enough to demonstrate that a large number of people, even the majority of people, think the filter is a bad idea. Defeating the filter means convincing Labor that it will have electoral consequences worse than pissing off the Christian lobby.

Filter opponents appear to believe Twitter, online petitions, protests and letter-writing campaigns will be enough.

However, 10,000 people blacking out their avatars, retweeting blog posts and furiously agreeing with each other on Twitter merely adds to the cacophony of the echo chamber; it has no effect in the real world.

The closed circle of the Australian Twitterati and their friends in the technology and political media might well believe everyone is against the internet filter since everyone they know is talking about it.

But in the mainstream media, the filter was a lower-order news item on the day it was announced and has since almost disappeared.

This level of self-obsession reached the point where filter opponents spent a day debating whether #nocleanfeed or #openinternet was a more useful hashtag, as if nomenclature were the only thing holding the movement back.

Meanwhile Senator Conroy, the ACL's Jim Wallace and almost every mainstream media outlet were implying they were child pornographers.

I strongly believe the anti-filter lobby can succeed, but it must change tactics. Unless it stops preaching to the choir and starts getting into the serious business of lobbying, it is doomed to failure.