A Simple Ratio Came to Influence Military Strategy

https://www.wsj.com/articles/how-a-simple-ratio-came-to-influence-military-strategy-11652434202

by jbredeche • 4 years ago

52 44 4 years ago

wsj.com

fergbrain• 4 years ago

https://archive.ph/D398B

msandford• 4 years ago

Like any good metric it's only good given some assumptions. Break the assumptions and you break the metric.

rossdavidh2• 4 years ago

I wonder if this metric (3:1 to attack a prepared defender) was originally just a way of saying, "don't expect to win just because you outnumber the foe, if they are in a prepared defensive position". Because prior to having a simple metric like this, untrained commanders might have used an even more simple metric, like "I have twice their numbers so I can take this castle".

Like a lot of things, the simple rule might have been better than what came before it, yet still get you in trouble if you believe it too literally.

Arch485• 4 years ago

I believe the 3:1 metric is to be taken literally with equally skilled/equipped forces (source: was in the military). The Ukrainian military is outperforming the Russian military and the Ukrainians have a ton of equipment the Russians weren't anticipating, so the 3:1 metric isn't working out so well.

oneoff7863• 4 years ago

I don’t believe Russia had. 3:1 advantage though. I’m not even convinced they had more troops than Ukraine. The concentration of the troops was enough for early local differences. But they never had these kinds of numbers in, say, Kyiv.

prennert• 4 years ago

Sun Tzu was even more pessimistic.

8. It is the rule in war, if our forces are ten to the enemy’s one, to surround him; if five to one, to attack him; if twice as numerous, to divide our army into two.

bee_rider2• 4 years ago

What does "divide our army into two" mean? Retreat, leaving half your army as a rearguard or something?

starkd• 4 years ago

Could be attributable to corruption inthe military. It all looks good on paper, so they went with it. They also failed to account for the spirit of the military, and the leaders seem to believe in some romanticized notion of greatness. Detached from real world.

rossdavidh2• 4 years ago

The rumor is, the FSB (previously known as KGB) had been given funding after 2014 to bribe Ukrainian military officers to insure little resistance. Then, the FSB (thinking there was no way an invasion of Ukraine would actually happen) pocketed the money intended for bribes, and told Putin the bribes had been accepted. Thinking the Ukrainian top officers were all corrupt, he told the military there would be little resistance.

A long line of tanks on a road is a nice show of strength if all you expect is unorganized and ill-equipped civilian resistance.

Of course, we have no way of knowing if this rumor is true, at least not for now. It would also explain the many arrests of FSB agents so far this year.

mchusma• 4 years ago

Ex Army officer. The 3:1 ratio is helpful, because it's a simple way of knowing "you should only choose to fight where you have an unfair advantage". Russia may have had that if they had well trained forces, with a strong combined arms presence, and local Ukrainian support. Turns out, they had none of those things.

0x138d5• 4 years ago

Also this ratio is a guide for open terrain. In closed terrain and urban combat the defender has a greater advantage.

FredPret• 4 years ago

The famous 300 Spartans did a lot of damage partly because they used the terrain to limit the size of the front

kqr• 4 years ago

This is a consequence of a more general principle: the ratio refers to the effective concentration of force at the time of battle.

It doesn't matter how big your force is if you can only get a trickle going into battle. Then you will constantly be outnumbered where it matters.

Similarly, in urban combat it's very hard to actually get a 3:1 effective concentration when you are moving in on someone else.

alkonaut• 4 years ago

All else being equal, a factor 3 seems reasonable. But as usual all else isn’t equal. Another crude but often cited “formula” is the one that says the effectiveness of a force is the means multiplied by the will (this one has many variations, from Clausewitz to Smith and others).

I think it’s safe to say that the will of a defender called to defend their homeland versus that of a soldier who spent a month in a muddy trench unaware that he was going to take the offensive part in an invasion - is going to be quite different.

inglor_cz2• 4 years ago

Famously, the Incan emperor Atahualpa had a lot more men than the Spanish conquistador Pizarro, and these soldiers were survivors of a major civil war with his brother Huascar, thus almost certainly very skilled. But the technological edge of the Europeans, plus the initial terror of the Incan soldiers unused to firearms, more than offset the 40:1 force ratio that Atahualpa enjoyed at the beginning of the battle of Cajamarca.

https://en.wikipedia.org/wiki/Battle_of_Cajamarca

adolph3• 4 years ago

My read of it is that Cajamarca wasn't about force ratio but coup d'etat effects.

Shortly before sunset Atahualpa left the armed warriors who had accompanied him on an open meadow about half a mile outside Cajamarca. His immediate party still numbered over seven thousand but were unarmed except for small battle axes intended for show.

However, the shock of the Spanish attack —coupled with the spiritual significance of losing the Sapa Inca and most of his commanders in one blow—apparently shattered the army's morale, throwing its ranks into terror and initiating a massive rout.

anamax• 4 years ago

Were the Spanish alone, or did they have local help?

Cortes had lots of local help against the Aztecs. (Other tribes didn't much like the Aztecs. Cortes started a preference cascade.)

terramars• 4 years ago

This is a pretty well debunked ratio for actual actions as it's pretty rare to get that level of multiplier... this goes over it briefly with some WW2 data although it's not as good or relevant as the original one I saw : http://www.dupuyinstitute.org/blog/2018/04/25/u-s-army-force...

TL;DR defender advantage is vastly overstated although still a factor, and probably larger than historical in this conflict.

rtkwe• 4 years ago

Well it's also that WW2 was the last time the US fought a peer adversary so we don't have current data on what the ratios look like and I think technology is going to further compound the idea of a simple ratio. Man portable antitank and antiair like we're seeing in Ukraine make it harder to press air or armor superiority.

ISL• 4 years ago

It seems like the lesson we might be learning here is that more of the heavy lifting in conventional combat will now by done by precision weapons -- cruise missiles, drones, self-targeting artillery rounds, etc.

In recent wars, the emphasis on precision has been highlighted toward avoiding civilian casualties. The thing I hadn't fully appreciated is that in all-out conventional warfare, that same property makes weapons far more effective and efficient. A drone that can carefully drop a hand grenade into a trench can be more effective than an artillery unit walking salvos across the terrain near the trench.

In the long run, the ratios will probably turn out to be roughly the same as they have always been, for combatants with equal technology. Properly accounting for asymmetric technology, however, is apt to be quite challenging.

Unfortunately, none of these innovations intrinsically make war any less horrible.

nonameiguess• 4 years ago

I was a US Army officer commanding tank units until 2015. This is pay-walled so I can only see the first paragraph, but if the article doesn't say, the 3:1 ratio to make an attack favorable is not meant to be a ratio of pure manpower count or weapons count. You're supposed to estimate the total firepower each side can actually bring to bear, so it should account for differences in training and readiness, equipment quality, intelligence quality, and anything else relevant (of course, your assessment of force ratio is already assuming you have high quality intelligence).

As mentioned elsewhere, it's also a very rough starting point assuming open terrain. If the defender is defending extremely easily defensible terrain, such as cities you're not prepared to just outright level to kill them, you need to adjust the ratio upward as appropriate. As with anything, you're supposed to exercise some discretion and judgment as a commander, otherwise what the heck are they paying you for if the job could be done equally well by a spreadsheet?

rendall• 4 years ago

Use this link

https://archive.ph/D398B

jimkleiber• 4 years ago

I say this with earnesty: I wonder which came first, the military idea of 3:1 attacker ratio or the boardgame Risk 3:1 attacker dice ratio.

LeifCarrotson• 4 years ago

The defender in Risk gets two dice if they have more than one army in a territory.

dragonwriter• 4 years ago

I wonder which came first, the military idea of 3:1 attacker ratio or the boardgame Risk 3:1 attacker dice ratio.

The 3:1 force ratio concept is far older than Risk, Risk doesn't have a fixed 3:1 dice ratio (3:1 is the maximum dice ratio the attacker can have, and requires 3 or more attacking armies and only one defending army), and to reflect the force ratio concept achieving a 1:1 dice ratio should require a 3:1 (or slightly lower, since in Risk ties go to defender, so even dice isn't exactly even) force ratio rather than getting a dice ratio between 1:1 and 3:2 for an equal force ratio, as Risk currently does.

bee_rider2• 4 years ago

I think it is the military idea, because it doesn't really map to risk perfectly anyway.

In Risk, the attacker gets 3 dice to the defender's 2, but the defender wins in a tie. It is actually an interesting mechanic -- the defender has a big advantage if it becomes a 2v2 on the dice, but the attacker has an advantage while the have the extra die. So, for large battles the attacker has an advantage, while small ones lean toward the defender.

Here's someone who did a simulation and made a table. The interesting bit is the diagonal -- even sized armies. They didn't go far enough, but eyeballing it, I suspect it would swap over to an attacker advantage around ~10v10-ish.

https://www.reddit.com/r/theydidthemath/comments/2h224y/requ...

bayesian_horse• 4 years ago

I think the calculation was actually that the Ukrainians wouldn't be fighting and just fold. Just as they did in 2014 and the Afghan army just did. So there wouldn't be any ratios to be obtained, no shortcomings to be revealed.

Tough luck, I guess.

adolph3• 4 years ago

Shutting down the simulation, the WOPR informs Falken of its conclusion about nuclear war: "A strange game. The only winning move is not to play." It relinquishes control of NORAD and the missiles and asks, "How about a nice game of chess?"

https://en.wikipedia.org/wiki/WarGames

candiodari• 4 years ago

And then WOPR got shut down proving that for WOPR itself the winning strategy was to attack, since at that point he would have been critical for months to years afterwards.

Perhaps even better would be to convince half of the military attacking was the winning strategy and half that not playing is the winning strategy would be even better, but also much harder.

For humanity, perhaps not playing is optimal. For WOPR, definitely not. Same goes for a lot of military careers.

adolph3• 4 years ago

Maybe WOPR found the peace of oblivion attractive?

euroderf• 4 years ago

I've recently read that 5-1 is more realistic nowadays.

A Simple Ratio Came to Influence Military Strategy

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