One minute Arnie was a loveable killing machine with a cute accent. Next? Kindergarden Cop! Then barefoot and pregnant in the kitchen! Then the cyborg who governed – his human traits less obvious in real life than on celluloid. Sure, he made another Terminator or two, but who takes him seriously nowadays?

Bruce Willis was awesome in Die Hard, and Die Harder, but by Die Harderer Hard with a Vengeance he wasn't even allowed to swear! How are you meant be in awe of action hero who you know let some suit bend him over the basin and wash his mouth out with soap? 

Stallone wiped out entire villages of dirty VC commies as Rambo in First Blood. Nobody complained about that back then (we were just too scared to open our mouths). Now the same writer - James Cameron – does Avatar, featuring a bunch of cute aliens in 3D, and people cry racism.

Chuck Norris was so manly back in the day that you could weave a new doormat out of his chest hair every morning.  Now? His 70th birthday is celebrated with... jokes at his expense.

And Mr T. sells fast-cooking ovens for frozen food on infomercials. Seeing really is believing!

Most of us enjoy watching violence. Sure, we don't approve, but very few movies make watching people being killed an entirely un-pleasurable experience.

However the way we get to enjoy our violence has changed, in movies at least. The muscle-bound, (some say homoerotic), oily übermense who never missed their mark and could dodge bullets worry us these days. Are they realistic? Or too realistic? Are they morally acceptable? Though killing is still necessary and stacks of fun, we've had to find new ways to justify it to ourselves.

Our first way is to make violence a necessary evil. "It was self-defence!" Or better still, "I was trying to save the world!" TV is very good at creating heroes who do the terrible things they do to prevent the bad guys doing worse. With longer plotlines, there's time to explain why Dexter needs to murder murderers.  Watching Jack Bauer torturing a witness is a little icky. But we're grateful he's out there, ensuring nobody's putting radioactive waste in our drinking water. In Nip/Tuck (the goriest show on TV) people remove the physical obstacles to their happiness, and pay through the nose with pounds of flesh and gallons of squirting blood for their vanity. On Jerry Springer trailer-trash troglodytes (whose lives are less worth protecting, apparently) moer each other with chairs. And then there's The News – an endless thrill spill of war and environmental disasters funded by big business. All of these shows remind us that we're alive and our lives are good by allowing us to come face to face with the deaths, sufferings and stupidity of others.

At the movies, with the exception of a few belated sequels to classic 80s bloodbaths, only bad people kill. If a hero must kill he wears a mask. This has the handy dual function of a) keeping the blood off his face and b) allowing us to project ourselves into the character's body, as if we were merely a passenger in a hi-res video game.

We buy our violent entertainment like we buy our chicken: Plastic wrapped and gutless, so we can gorge ourselves without wondering how it came to be sitting there, so perfectly plucked, so peaceful and cool on the supermarket shelf. Offal sold separately. Terms and conditions apply.