Most people who don't work in film, music or digital technology companies probably hadn't heard of Sopa, the Stop Online Piracy Act, before this week – that is until Wikipedia's founder decided to black out all its English-language pages for a day in protest against proposed US legislation to combat the trafficking of copyrighted material online. It made me wonder what would happen if all the content-creation industries blocked access to all their products for a day to demonstrate what would happen if they couldn't make any money from their work owing to rogue sites. There'd be no music, no television, no film, no books, no radio. What would you miss the most – culture or Wikipedia?

And for those of you claiming people would make music even if they didn't make any money from it, let's say we'd only suspend music made by professionals and that created thanks to investment by a company hoping to make its money back (that includes major and indie labels). The only music available would be music made by hobbyists. Would you miss Wikipedia more than you'd miss music released by record labels?

Of course it would be impossible for musicians to pull off such a stunt. They could only blackout media outlets that actually have a licence for music. There's plenty of unlicensed content on YouTube, and Google – YouTube's owner – only blocks it when it wants to. For example, when it wants to force business negotiations to tilt in its favour, as it did last time it negotiated with PRS for Music (interestingly, Google doesn't have a deal with Stim, the Swedish version of PRS, and it hasn't blocked any Stim-related videos in Sweden).

The main argument used by the anti-Sopa lobby is its proposal to block foreign sites carrying unlicensed material is censorship and curtails freedom of speech (though the Tharir Square protesters seemed to get their message out without recourse to putting new albums on to Pirate Bay). Regarding censorship, the Register's Andrew Orlowski pointed out in his analysis of the issue that Google itself is a web censor on a significant scale, making 11m sites disappear just last year, on a whim – without legal due process or transparency.

But the main problem with preventing piracy is not lack of legislation, it's the inability to enforce it when it comes to foreign sites, and few artists dare even speak out about the issue. I have received online death threats for speaking my mind, and recently a Finnish anti-piracy group received a bomb threat for its role in blocking Pirate Bay in Finland. An owner of one photographic agency told the Washington Post that after her name appeared on a list of Sopa supporters she began getting emails like this one: "I AM INFORMING MY FAMILY AND FRIENDS THAT IF THEY SUPPORT your firm I WILL MAKE LIFE DIFFICULT FOR THEM." All in the name of free speech.

I'm not a fan of suing people who use rogue sites; I'd much rather focus on the sites themselves. In Europe, ISPs in Denmark have blocked Pirate Bay after those behind the site were convicted (twice) in Swedish courts, yet Swedish ISPs refuse to do so. In the UK, BT blocked Newzbin after told to do so by the courts. Does that make these countries dictatorships? Of course not.

I'm not saying Sopa is perfect, and I'm sure it'll go through some changes before being passed (it appears the sections relating to blocking sites will be pulled), but what gets me is that its opponents reject any attempt to curb piracy. They think they have nothing to lose from piracy, so why should they care? Many anti-Sopa lobbyists even gain from piracy – not only does Google net millions of dollars from its ad networks thanks to the unlicensed content it helps users find, but Google can also useit as a negotiating tool with the music industry, telling artists "it's better than piracy" as it offers them the tiny crumbs falling off its multi-billion dollar table.

Instead of offering any sort of constructive ideas on how to curb piracy, Sopa's opponents say the music industry should move with the times, not hold on to an old business model. Yet, despite many of them declaring themselves entrepreneurs, they can't offer any valid suggestions of what that business model might be. Quality content is not cheap to make, hence why online ad-funding has not managed to save some of the world's best newspapers from running at a loss and cutting staff.

Spotify is not yet profitable, and dismay with the paltry royalties it pays artist and songwriters has been widely documented. Stim and PRS gave Spotify a break on royalty rates to help it get off the ground – alienating their own members, the songwriters, in the process. The collection societies defended their decision by saying rates would get better as the music service converted users into subscribers. But if music fans turn to rogue sites (I'm talking to you Grooveshark) as soon as Spotify tries to charge more,then Spotify will fail. So, in effect, piracy prevents the development of legitimate sites.

Let me finish with what my fellow songwriter Rick Carnes told me recently. He was speaking on a panel about copyright, the internet and piracy. On one side were people from the culture industry, on the other the technophiles and anti-copyright campaigners – and then there was an economist. All through the debate he said nothing. When asked why, he said he couldn't debate an issue that used a starting point – that the culture industry should compete with piracy instead of fighting it, while being denied ownership of their "product" – at which the basics of a successful economy had been taken away.

He said in a capitalist society consumers are taughtto get the best value they can. Therefore "free" will always attract the most consumers. But it is absurd to suggest "free" will support the production of goods and services, he continued. The laws protecting private property were established because "free" was not working to create progress. The devastation you are seeing in the music industry is exactly what you would expect when people lose the protection of their property. Anarchy results and the market collapses, he concluded.

We may not see the repercussions of it now, but a Wikipedia-style blackout of all music, television and film – apart from hobbyist material – would give a taste of what's to come if we do nothing. Maybe then these technology companies would realise there is something to lose, even for them. Believe it or not, there's a limit to how many cute animal videos one can watch on YouTube.