There's a classic story by Robert Sheckley that's stayed with me for some reason. Fool's Mate appeared in Astounding Science Fiction in March 1953. Here's the pitch (SPOILER ALERT): two mighty space armadas have faced off against each other for nearly a year, without coming to an all-out engagement. But the officers aboard Earth's fleet are cracking up, going slowly insane because they know they're going to be blasted out of existence. In the battle to come, every move the fleets make is pre-ordained by ultra-logical computer systems – and a tiny flaw in their take-off formation means Earth's ships are predestined to be destroyed.

The stalemate is broken by some smart lateral thinking, when one of the gunnery officers who's been driven mad by the uncertainty is given the chance to press some pretty buttons entirely at random. The enemy computers can't find a pattern and don't know how to respond, and Earth is victorious.

Actually, I know exactly why I've been thinking of that story. Forget about the dodgy understanding of mental illness (it was written 65 years ago, after all). It's about the disruptive effect of someone who is completely unfettered by logic, who has no regard for consequences, who operates according to a purely internal system of reasoning that's entirely disconnected from reality – and who has enormous power at his fingertips.

Yes: Donald Trump has withdrawn from the Iran deal against the advice of the military, his own diplomats, the nations of Europe, his allies in the Middle East (Israel excepted) and pretty much everyone. The disruption to the world order has been seismic. Not the least damage is to the idea that the US is trustworthy: Iran complied with the terms of the deal and America tore it up anyway. The world is suddenly far, far less safe, and the madman's still locked in the control room pushing buttons.

That's what it looks like, anyway. But there's another point of view.

The cool logic of trained negotiators may have stopped Iran acquiring nuclear weapons. But it has not stopped millions of deaths in the Middle East, in Yemen, Syria and Iraq – and many of them can be laid right at Iran's door. The fact that it's not a nuclear power doesn't mean it's 'good' – on the contrary. The wretched hestitancy and ineffectual posturing of the US and Britain in Syria under Obama and Cameron led to nothing but more bloodshed and another win for Iran. The civil war in Yemen, which has caused unimaginable hardship for civilians, is of Iran's making: it has armed the Houthi rebels against the legitimate government in pursuance of its quest for regional domination. It funds Hezbollah in Lebanon.

Does this mean Trump was right to tear up the deal? No – it's just another point of view, illustrating the enormous complexity of the issue and warning armchair strategists that they should be wary of opining too positively on things about which they may not have full information.

But the point of our story is this: none of the computers' tactical calculations made sense when the random element was introduced, and that's what Trump is doing. He is entirely unpredictable and unmanageable – and it's just possible that his chaos diplomacy might break apart an international consensus that has so far remained utterly indifferent to the deaths of millions.

We may already have seen one possible result of this approach. It might be Trump's childish aggression towards Kim Jong Un, when he appeared in all seriousness to threaten a nuclear strike on North Korea, that helped drive Kim to the negotiating table: Kim couldn't be sure that Trump wouldn't do it. Might his virulent hostility to Iran have the same effect? We don't know – and that's the point.

The thought of someone with as little talent for governing as Trump handed such a position of influence in world affairs is deeply troubling. But that's what we've got – and we have to hope and pray that since the logical and reasoned approach of the professionals has delivered nothing but horror, chaos diplomacy might actually work.

Follow Mark Woods on Twitter: @RevMarkWoods