March 17, 2021 - 7:00am
The new integrated defence review has been released, and there’s a line in it which is interesting. It is “likely”, it says, that a terrorist group will launch a “successful CRBN [chemical, radiological, biological or nuclear] attack by 2030”.
That sounds bad. But … what does it mean?
I’m not sure. For one thing, it’s not clear whether it means a successful attack in the UK, or a successful attack anywhere. Obviously, an attack somewhere in the world is more likely than attack in a particular place in the world.
Also, it’s not clear what “likely” means. When I hear the word “likely” I tend to assume it means “more likely than not”, i.e. a greater than 50% chance; but people interpret these words differently. (“A real possibility” means a 20% chance to some people and an 80% chance to others, for instance.)
Third, “a successful CRBN attack” makes us think of nuclear bombs in the centre of London. It’s worth remembering, though, that the Tokyo subway sarin attack of 1995 would count as a “CRBN attack”. It was pretty nasty — 13 people died.
But the fact that they were CRBN doesn’t make them worse. You could very easily kill 13 people with an entirely conventional, old-fashioned bomb or gun, none of this fancy stuff at all, and in fact quite a few people have in the not-too-distant past. A 15-kiloton atomic bomb in Canary Wharf would be a CRBN attack, but so were the Salisbury novichok poisonings. It’s a category that contains a lot of very dissimilar things. I’d say it’s more than likely — it’s damn near certain, in fact — that something you could describe as a “chemical attack” will happen somewhere in the world by 2050, and that it’s more than 50% likely that we’ll see one in the UK.
So how likely would a real disaster be? A nuclear bomb in a city?
Interestingly, we can make a decent stab at this. Terrorist attacks, like earthquakes and meteorite strikes, follow a power-law distribution. Small ones are common, but larger ones get rapidly rarer, with (according to this 2006 paper, anyway) a scaling parameter of 2.5. That sounds complicated but it just means “a terrorist attack that’s twice as large is about 2 to the power 2.5 (about 5.5) times as unlikely”. This paper finds something similar.
If I’ve understood it correctly (quite a big if), it works out you can expect to see X terrorist attacks with Y deaths each year, where X is the total average number of attacks per year multiplied by Y^-2.5.
The 2006 paper said that between 1968 and 2005 there were about 10,000 terrorist events that killed or injured one or more victims, up to and including the 1998 Nairobi car bombs that injured at least 4,000 people. That’s about 270 a year.
Eyeballing their graph:
About one in every 30 of those attacks should kill 10 or more people, so about eight a year. About one in every 500 should kill 100 or more, so that’s about one every two years. About one in every 10,000 of those attacks should kill 1,000 or more. So that’s about one every 40 years.
How about extrapolating to really big attacks, city-killers, 10,000 or more? The sort that would take a nuclear bomb or something really catastrophic?
Well: it looks, if I really crudely draw the line down by holding a pencil against my computer screen, as though it’d be somewhere in the 10^-5 region: that is, about one in every 100,000 of these events will kill more than 10,000 people. Given 270 events a year, that’s about one every 370 years. So it could happen, but it’s not very likely in any given year.
A couple of caveats: first, power law distributions become increasingly useless for predictions at the higher ends of the distribution; and second, never trust a man who has tried to estimate a number by holding a pencil against his computer screen. But it’s probably within that order of magnitude.
Of course, there are other ways things can go terribly wrong without terrorists needing to get involved. A good old-fashioned world war would do it. The forecast aggregator Metaculus thinks there’s a 20% chance of two or more nuclear bombs being detonated in war by 2050 and a 17% chance of “World War Three” by the same time. Those sound like scary figures. But if we’re interested in “successful CRBN attacks”, that’s probably the sort of likelihood we’re talking about.
Update: This article originally stated that at least 4,000 people died in the 1998 Nairobi killings. That was incorrect, and has now been amended to say that at least 4,000 injuries occurred.
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SubscribeSurely the lesson that has been learned is that a mild virus can bring the West to a standstill. The West has the incapacity to judge and manage risk. It doesn’t matter if something has a 1 in 1000 chance of killing you, or 1 in 100 or 1 in 10. RISK HAS TO BE ELIMINATED!!!!
It requires far simpler technology to develop biological weapons than nuclear weapons. Chemical weapons are somewhere in between, but difficult to deliver en-masse.
The path for terrorists is a fairly simple lab manned with virologists trained in western universities. This investment would pay back many times over. Even a fairly mild virus like covid 19 caused havoc. Imagine if they struck gold and got their hands on something more deadly.
Gain of function. Covid19
I agree that there are many bad people out there who have seen the pandemic and the global chaos it’s caused. The problem with creating something in your own lab is that you’d need to make sure that you had a cure for yourself and your own kind first. There’s no point in wiping out the entire human race on the planet … or is there ?
You haven’t factored in the number of people receiving the Astra-Zeneca vaccine!
It is not very useful making meaningless estimates. Terrorist attacks do not follow a simple law of nature, and cannot be predicted from a probability distribution. Their rate could go massively up or down depending on many factors, for example whether an organisation facilitating them crops up or is defeated. Extrapolating from data gathered over less than 40 years and concluding that something is expected to happen once in 370 years is bad science, in the same way that it was bad science pre-2008 banking crisis to estimate a financial system breakdown was something that would happen once in a million years.
As for the forecasts from Metaculus about how likely is deployment of nuclear weapons or WWIII breakout: apparently estimates are made by random people logging on and twiddling a bar ranging from 1% to 99%. The output might say something about attitudes of the people taking part in forecasting, but it does not tell us anything about the likelihood of the events in question.
I think Mr Chivers should be invoking the term “black swan event”. And I think some economist bloke wrote a book on this.
Hey UnHerd admins, why has your system blocked my completely innocuous post please? There is nothing even remotely offensive in there – no bad words, no insults to anyone, nothing. What’s the trigger?
The whole ‘system’ has been appalling since they fired DISQUS a couple of months ago now.
I really miss the cold war
A nuclear bomb in a city, a disaster?
It all depends on which city.
Bradford or Birmingham and some would regard it as a fortunate event. lol
Another great reset..
Not Slough?
I sometimes wonder what Betjeman would think of how some 21st century English towns turned out…
Terrible in most cases.
I imagine he would be kept busy with a lot more poems to write.
Thanks to nano-technology the smallest nuclear weapon weighs about 35kg, and could be fitted into a rucksack.
For the ‘delivery system’ all you need is a fit individual who is not afraid of death, to take the lift (elevator) to the summit of say the Empire State Building and detonate!
The “bucket of instant sunshine” as the saying goes.
Hi. First, I’ll make the caveat which you’ve already made that this is very much a back of the envelope big extrapolation exercise. Still, I think it’s useful to follow the logic through and I’m glad that you wrote your article.
Let’s go ahead and make the assumption that a -2.5 power law applies all the way up to arbitrarily massive events (again, quite an assumption). Also, let’s just stick with your assumption of 270 attacks per year (although this can be easily changed). It’s perhaps worth pointing out that we’re implicitly assuming here that all of the 270 events are covered by the 2.5 power law although part of the usual power law estimation is some minimum size below which there is no claim that a power law fits and above which there is some claim that it does. The point here is that some fraction of the annual set of events would normally fall outside (in particular, below) the scope of the estimated power law.
With these assumption in place, a few lines of calculus (happy to share) leads to the conclusion that the expected number of people killed in terrorist events of size S or greater per year equals 810 (this comes from 3*270) divided by the square root of S. From this you can quickly calculate, e.g., that the expected number of people dying in a given year in terrorist attacks in which at least 100,000 people are killed is 2.6. Of course, this very low number is because IF the power law continues to fit all the way up there then attacks of such sizes are exceedingly rare.
Of course, we have no data whatsoever on terrorist attacks remotely close to this size so, again, this is all quite an extrapolation. It’s also worth pointing out that surprisingly much changes if the power law exponent drops below 2.0 in absolute value (i.e., if it’s -1.9). On the other hand, making policy base on a likelihood of such a massive attack does strike me as pretty alarmist.
The entire debate around proliferation is now irrelevant – bypassed. Let me explain my reasoning. When nukes were first created in the 40s, the great fear was proliferation to countries under capricious despots – every tinpot would acquire them. Turned out, it wasn’t as simple as that – the bar over which most countries couldn’t jump was technology. It requires high-end precision mechanics, device physics and electronics. It requires physicists and rocket scientists. It requires very sophisticated governmental logistical and security systems to manage arsenals safely.
Very few countries had the necessary scientific and administrative heft, so the nuclear divide persisted, right up to the mid 2000s.
But the march of technology, see, so most of the components needed to make nukes and to a lesser extent rockets are now available off the shelf. North Korea will certainly have used US and Japanese chips, precision engineering from the UK, Swiss etc, software bought from Israel etc. So a whole tranche of second and third tier countries, are now capable of building nukes in short order. And the unpalatable truth is, this means *all* the tinpots of the world are likely this close to building nukes themselves. The only reason they wouldn’t is, it’s very expensive, and a bog standard tinpot would much rather enrich themselves with the money.
It may be the equivalent of handing a flick-knife to every toddler as they set off to nursery, but it’s not stoppable.
Chivers said: “But the fact that they were CRBN doesn’t make them worse.”
I’ve always liked Chivers – mostly because he really does understand statistics, but I think he is wrong in the above quoted remark.
Some half @rsed poison or dirty bomb attack need not be very sophisticated and therefore is more likely, but could create a very difficult and expensive clean up job afterwards. We know from the Russian nerve agent attack in Salisbury that the clean up costs can be massive. I won’t go into details but making some kind of poison spreading device is not rocket science.
He understands statistics? Ask him what the ARR is on the vaccines. Lol
I see possible triggers for WWIII conventionally could be
Taiwan invaded by China
India invaded by China
Indian rivers intercepted in Tibet and diverted towards China
China is moving towards domination and a clash may be inevitable because of its very distinctive social contract. This is the idea which the Chinese leadership is putting around.
Of course there could be other types of confrontation: So there you are a WWIII could be fought by ways of “attacks” on us from inside the enemy (The Marxist China Virus) and made from inside our societies, more precisely from inside the minds of the poor snow-flakes by manufacturing Marxist Wokes inside the “free societies” which can render us out of action or inferior without the need to fire a Marxist army single shot, the weapons of such a war would be: biological and information! Our meritocracies could be whipped out!
We would still have no ways to deal with the conflict in which we may even seem to be in already.
As I say, some speculators may even argue that WWIII may have already started by China sacrificing some “pieces” in this “chess game” and with this “making an innocent attack” on the rest of the world already with no need to fire a shot and leaving all resources intact for it to take over at a later stage.
UK needs to go back in to biological and chemical warfare field fast and also in to the field of information not only to defend its integrity but also to understand its use in fed back systems like minds of the poor snow flakes, which can be veritable lose canons in such a war.
We stare at how such an attack could be made and for which retaliation would be impossible because this would be made unjustifiable. It would be genocide but hey! What problem is that for Marxism!
The first Marxist national leaders would have tried honestly to implement the ideas of Marx and in most cases would have had to come out of a genocide which they would have caused themselves by the fixing of outcomes, genocides for the Marxists are water of the ducks back, totally inevitable.
The genocide has to come by necessity when trying to apply Marx’s open loop system to the social contract. Soon such a society will hit a wall somewhere because it is flying around and has no feedback to correct it’s flight path like market competition.
To go any further the two big Marxist Empires of Russia and China have kept the tyrannies but have given up marching towards Communism and done a U turn and have brought back a corrupt form of capitalism. The ultimate control rests with the Marxist Tyranny not so much with the market, but at least the market controls when it is not a challenge to the tyranny making the state a survivable proposition for most of its inhabitants which no longer are the slaves of only Marxist forced outcomes, the residents don’t need to go jumping walls, barbed wire, dodging bullets and minefields to get in to areas controlled mostly by meritocracies of the old British Empire and its descendants, so maligned today ironically but understandably because meritocracy is poison to the Marxist woke.
The Marxist woke, in turn as Lenin would have described them much more accurately: “the useful idiots” are there also to undermine meritocracies without firing a shot by any Marxist armies. The Marxists only have to give money to places like Cambridge and if traitors are caught even they will “escape” no Elizabeth I will come and chop heads off no sir! They will end their lives in sunny Moscow or now in Beijing.
The woke by tying up the hands of “free societies” by using intelligent Marxists thinkers from places like Cambridge to take the glorious past of our meritocracies out of context and out of time, then putting their false conclusions before the light weight “snow-flakes” of today they seriously block the progress of the rivals to the Marxist Empires which are also totally “innocent” and outside the free societies under attack, but working also inside the free societies abusing the freedom and democracy and supporting the worst tyrannies of the planet in this way.
This is also done bloodlessly, rarely a shot is fired and the argument is won by exploiting any grievance and by taking away all what was happening at the same time as those “bad things” and then when put before the unsuspecting “snow flake” the poor snow flake is hit by cognitive dissonance and goes in to one! Out come the plackards!
This of course generates from inside the most outrageous regulations, voting intentions, laws, you name it! And the free societies start to cut their own throats all by themselves. So Marxists here are the masters of feedback, and instead of putting the best elements in to the feedback of the West they have infiltrated veritable enemies of the West in to the control of education, judiciary, legislature (they all have degrees from “you know where”) and so on which even seek to purge any form patriotism for the sake “righteous woke ideals” which are totally against the very idea of meritocracy or freedom of opportunity and want nothing but to fix mostly a bad outcome and to keep that result there messing up everything else in society if possible overthrowing the State itself.
This is all what Marx would have recommended, so Rhodes must fall, and when he falls Rhodesia will become Zimbabwe, and the breabasket of Africa will no longer feed Africa or even Zimbabwe but will parasitically start to consume the help of the world as it won’t even be able to feed itself, and the Rhodesians will want British rule and will make their way here with their children in small boats at a great risk to Europe and the woke will come and tell the immigrant how good their culture really is and failure will be brought in to Europe compounding problems. By destroying the European Empires the Marxists generate a catastrophe and here we are in our pandemic and surrounded by wokes. Is this what WWIII looks like? How many more attacks can we take before we fall?
Can you put that on half a sheet of A4 and leave it in Winston’s in tray?
Fauci and Gates already did. This is WW3. The great reset.
Looking at World war one and world war two it would be easy to say that two was in fact,just a continuation of one with a impolite pause for a political breath between.
Indeed in many respects world wars are not separate event’s they are a continuation of man’s odd desired to inflict the maximum horror on enemies as possible and if that involves chemical, biological or big bang machines then so be it.
It all gets complicated when the weapon of choice becomes not just a threat to enemies, but also is so awesome in power that it is no longer controllable by the instigators.
Mutual destruction is where we are today and there are many theories that it is that part of the equation which has prevented level three, after all man may be stupid but not that stupid.
Or is he?
I won’t end by suggesting that Covid 19 was an experiment gone wrong and it escaped the control of its designers or that it was in fact a deliberate attack that reaped havoc on the world, but what was the point if true after all it was not and could not be selectively targeted.
So what’s next for man, who knows ,will viruses be the weapons of mere terrorism, perhaps.
China seems like a threat but is the other side of the world and t feels surrounded by states that control their seaways preventing access to raw materials. That needs calming down and some acceptance. But they want order and equality.The issue is and will be religious fanatics in the Middle East who prefer death to life.