Hilary Benn has quite a robust interpretation of the parable of the Good Samaritan. In his version, the Samaritan doesn’t just help the traveller who’s been mugged, he volunteers to seek out and blow the living crap out of the poor chap’s assailants, despite the obvious practical difficulties of knowing who they are and tracking them down. This is the Good Samaritan as played by Charles Bronson. But to do anything less, the shadow foreign secretary apparently believes – as revealed when he quoted the parable while urging his fellow MPs to bomb Syria last week — would be to “walk by on the other side of the road”.

Benn’s claim that only by releasing explosives over another large section of the Middle East are we truly respecting Jesus’s exhortation to love our neighbour as ourselves was the most ingenious piece of rhetoric in what has been quite the rhetorical purple patch for British politics.

It’s like they’re jostling to make soundbites worthy of the trailer for a Jack Ryan movie

Benn’s speech was full of gems, calling Isis (or IS or Isil or Daesh – there are almost as many words for it as there are for shagging) “fascists”. “They hold us in contempt. They hold our values in contempt… They hold our democracy… in contempt… And my view, Mr Speaker, is that we must now confront this evil.” Close your eyes and feel those Churchillian rhythms.

But Hilary didn’t have the monopoly on portentous utterances. Alan Johnson said there was “a real and present danger”. Another Labour MP, Dan Jarvis declared “there is still a dignity in uniting with our allies in common cause against a common enemy in defence of our common humanity”, a phrase he might have saved for when the House of Commons votes on a motion to fight back against the Martians.

David Cameron started the week saying that “the decision to take military action is one of the most serious a prime minister can make” – you could just sense how much he was looking forward to it – and the burden of seriousness seemed to lift pretty quickly as, by Tuesday, he was referring to those who opposed military action as “terrorist sympathisers”. And, after the Commons debate had gone the government’s way, Philip Hammond, like an ageing and kindly gunslinger, declared “Britain is safer tonight”.

Illustration by David Foldvari.

It’s like they’re jostling to make soundbites worthy of the trailer for a Jack Ryan movie. It’s all serious and stirring, but also inappropriately slightly fun. Frankie Boyle summed up my misgivings when he tweeted about Wednesday’s Commons debate: “Kind of disturbed by the palpable excitement in parliament. The truth is our politicians like wars because they make them feel important.”

I know that’s not true of all our politicians – and even when it is, it doesn’t mean they’d start a war for that reason alone. But the parliamentary atmosphere slightly reminded me of an occasion when I was helping install the set and lighting for a theatre show and someone started playing the soundtrack to Crimson Tide through the speakers. Suddenly everyone’s behaviour changed: it now felt like we were heroically erecting the set “against the odds”. Everything felt cheesily dramatic. In a similar way, I think some MPs were seduced by the dramatic beat of a war debate, and it’s ironic that Frankie Boyle was the one to point out that that’s in rather bad taste.

This isn’t to say that I think bombing Syria is the wrong course of action to take. I honestly have no idea. We’re already bombing Iraq (as usual), which I’d actually sort of forgotten but it does make bombing Syria as well seem like less of a big deal. The question, I suppose, is whether we can kill people who hate us at a faster rate than we make other people hate us by killing so many people. And I don’t know the answer to that.

By the way, I realise that the MPs who spoke against military action were probably only less melodramatic in their language because, when advocating appeasement or diplomacy, you have a much less rich rhetorical heritage to draw on. There’s no “Let’s stay out of the breach for now and really commit to the peace process” speech in Henry V.

The truth is that it may be impossible to know the best thing to do. There are situations when military action is disastrously counterproductive and situations when failing to intervene stores up trouble for later. It’ll be a long time before we know for sure which type this one is. Which is why the tone with which our deliberations are conducted might be quite important.

It’s an over-expressed, but often fair, criticism of modern politics that it’s all about style over substance – it’s all spin and we don’t focus on what should actually be done. Well, this issue is an exception: we are focusing on what should be done, but the spin has been rather neglected. And that’s a problem. The politicians need to be worrying less about whether bombing Syria will do any good (which nobody knows) and more on how they’re coming across. Because currently they’re coming across as people enjoying, and buoyed up by, the trappings and exercise of power. And that won’t do.

The most powerful person in Britain is the prime minister, not the Queen. That’s important not just because the choice of prime minister results from a democratic process, but because it separates real power from the paraphernalia of power. For both to be vested in the same person, the wisdom passed down in our constitution declares, is unseemly and unsafe. Being in charge of things feels good; that’s dangerous and only becomes more so if the person with the power also has the biggest chair, wears a gold hat and has to be bowed to. In a constitutional monarchy, real power is exercised with restraint, discretion and the trappings of service: powerful politicians “minister” to the crown, senior officials with billions to spend are known as “civil servants”.

These are presentational issues – symbolism and spin – yet the principles they represent are never more important than when the country doesn’t know what to do, but has to do something. The decision to bomb Syria may be a disaster, and the contrary decision might have been equally disastrous. But it would be easier to live with whatever the consequences turn out to be, if we felt the decision was made by conscientious public servants in a spirit of sober reluctance, rather than by enthusiastic patriots fizzing with martial verve.