Official UK government attempt at censorship

So, from what I can readily tell, the UK government has an injunction to stop http://badger-killers.co.uk/ from identifying people involved with the planned cull of badgers in the UK, the supposed intent of which is to prevent the spread of bovine TB. Presumably this is because animal rights activists in the UK have a track record of threatening violence / property damage against people involved in harming animals. Unfortunately this obviously also interferes with the normal and democratic ways in which the cull might be challenged.

FWIW, personally I say screw the the cull and the censorship attempt.

I thought that, in the U.S. at least, the use of a legal threat itself as extortion (as opposed the merits of a posited case, itself) was a serious "gray area" if not outright illegal in itself.

"We will take you to court to ruin you." (That being the primary objective, rather than the winning of whatever case is filed.) I imagine the UK has its own views on this, but wouldn't such an approach -- blatantly expressed -- receive serious scrutiny from any competent U.S. judge?