Tom Cruise is hauling his 50-year-old, somehow-still-ripped, self back onto cinema screens in December for thriller Jack Reacher. The full-length trailer was launched this week and, for people approaching this one without having read the popular series of novels, it focuses on a sort of justice-seeking loner with a background in military policing.

Naturally the emphasis is on ‘former military policeman’ because of course it’s pretty difficult to get anything done in this day and age when you’re forever restricted by that persistent irritation known to the common man as ‘the Law’. Best to learn the skills you need and then go rogue.

Jack Reacher is, the trailer tells us, a ‘ghost’ with military training who nobody can ever find, because of course like all great ex-military loners, he finds you. He likes to beat people up and he’s a great investigator – those two aren’t necessarily mutually exclusive. Either way, both appear handy when you’re looking for a fast-paced criminal investigation.

Crucially, the trailer makes clear that he is categorically not a hero, which of course instantly makes him a Reluctant Anti-Hero. Perhaps that’s more admirable than a guy who saunters into a police station, winks at the girl at reception and proclaims loudly: “S’up fellas? Everything’s cool now – the Reacher’s here! Did someone order Hero? With extra cheese? Yeah!”

Among the trailer’s best pantomime moments is a trembling voiceover as Reacher revs his Cool Car in a manner that can only be described as Cool: “He doesn’t care about the Law. He doesn’t care about proof. He only cares about what’s right.” This questionable ethos apparently makes him the good guy. Three lines loaded with potentially polarising rhetoric that somehow equate to an unwavering dedication to protecting the innocent and creating a better world.

Yet if President Obama was to say the same thing at the next presidential debate – “I don’t care about the Law. I don’t care about proof. I only care about what’s right!” – there would be a bit of a fall-out. Maybe he could make it work if he came onto the stage wearing a leather jacket and immediately punched Mitt Romney in the face?

Then again, Jack Reacher looks like Tom Cruise, and this of course makes him Utterly Trustworthy. Who needs little things like proof and laws when you’ve got the Cruiser heading the investigation? If he deputised for Judge Dredd we’d all be living in a weird future society with an unforgiving, streamlined and probably quite right-wing judicial system. We know instinctively that Reacher’s fighting for the common good and, crucially, he has a dashing leather jacket, the Cool Car and he’s happy to chase the villains in the rain without an umbrella; that’s real dedication. This all helps distract us from pertinent questions, like where are the actual police this whole time?

Well, they’re probably sitting around being rubbish and corrupt, or doing nerdy stuff like doggedly gathering evidence, building criminal cases that stick and acting within the confines of the Law. All without the benefit of looking anything like Tom Cruise or having a Cool Car.

Perhaps we can blame The Dark Knight for making flashy vigilante justice fashionable. Christopher Nolan’s blockbusting series offers a city of cops who are mostly incompetent and corrupt, and live in a world that was partly inspired by Michael Mann’s Heat. The police can’t handle the costumed villains so Batman roams around making snarky comments about how cops contaminate crime scenes and don’t have the cash to buy flashy crime-fighting toys. But all is well, because, as the Joker says, Batman is truly incorruptible and, well, he’s got this covered.

Varieties on the vigilante theme aren’t going away anytime soon. Liam Neeson’s been enjoying a career boost with the Taken movies and fans will know that cautious, law-abiding police work doesn’t get a lot of screen time there. Then there’s Gangster Squad, which will look at a group of determined cops going ‘off the reservation’ to take out Mickey Cohen’s gang in post-war Los Angeles.

The pesky Law may get in the way from time to time, but as long as they all follow Jack Reacher’s example and stay dedicated to what’s right, what can possibly go wrong?