Viacom’s $1bn lawsuit against YouTube, and its parent Google, poses the central question of the digital age: how can old laws be applied to new technologies, in ways that balance the rights of copyright owners with the public interest.

It is high time America’s courts answered that question, as it applies to the internet’s newest new thing: websites such as YouTube and MySpace, which host the user-generated content of millions of people – not to mention reams of content that is actually owned by somebody else.