Category Lethality

Test-Firing Early Modern Small Arms

Someone just brought this article to my attention: View of Material Culture and Military History: Test-Firing Early Modern Small Arms | Material Culture Review (

It is about a test firing of modern small arms conducted by the Austrian provincial armory in Graz, done in 1988-1989. They test fired 14 weapons from 1571 to 1750 and later, including 3 rifles. They used a standardized modern black-powder gunpowder in an amount determined during testing. They also tested three modern weapons for comparison.

A couple of tables from the article:

They also fired the guns into blocks of soap or gelatine, modern steel plate and 16th -century armor plate. For example, one flintlock musket left a cavity of 530 cm3 (cubed?) while a 5.65mm assault fire left a cavity of only 101 cm3 (see paragraphs 10 and 11 in the article).

They did fire a pistol at a part of the horse’s breastplate from 1570-1580, 2.8-3.0 mm, and it penetrated (paragraph 13) but the bullet was effectively stopped from injuring the wearer. The old breastplate performed better than 3mm of modern steel plate (see paragraph 12).

Common Use, Lineage, and Lethality

Below is an article from the UC Davis Law Review that references Trevor Dupuy 75 times, references me 9 times and references Susan Rich 8 times. The article is Common Use, Lineage, and Lethality by Darrell A. H. Miller & Jennifer Tucker: Microsoft Word – 55-5_Miller_Tucker.docx (

It still seems strange to me that a group of legal scholars are actually paying attention to the Theoretical Lethality Index (TLI) that Trevor Dupuy came up with in 1964, but we are flattered by the mention. This has been discussed before: Opinion: Now that guns can kill hundreds in minutes, Supreme Court should rethink the rights question | CNN. And then there is this: The Left’s Shark-Jumping Conclusions On NY Carry Case – Bearing Arms. These are all linked to this blog post: What Is The Relationship Between Rate of Fire and Military Effectiveness? | Mystics & Statistics (

I will be speaking at the Center for the Study of Guns and Society at Wesleyan University in Middleton, Conn. on 14-15 October 2022. The link to it is here: Center for the Study of Guns and Society – Wesleyan University-based center dedicated to interdisciplinary humanities study and teaching on the social and cultural history of firearms ( Click on this: Quantifying Arms Lethality in Historical Perspective – Center for the Study of Guns and Society ( Should be interesting. I have never actually attended an academic conference.

I gather the conference is open invitation:  Conference – Center for the Study of Guns and Society (

What Did James Mattis Mean by “Lethality?”

Then-Lt. Gen. James Mattis, commander of U.S. Marine Corps Forces, Central Command, speaks to Marines with Marine Wing Support Group 27, in Al Asad, Iraq, in May 2006. [Photo: Cpl. Zachary Dyer]

Ever since publication of the U.S. National Defense Strategy by then-Secretary of Defense James Mattis’s Defense Department in early 2018 made the term “lethality” a foundational principle, there has been an open-ended discussion as to what the term actually means.

In his recent memoir, co-written with Bing West, Call Sign Chaos: Learning to Lead (Random House, 2019), Mattis offered his own definition of lethality. Sort of.

At the beginning of Chapter 17 (pages 235-236), he wrote (emphasis added):


History presents many examples of militaries that forgot that their purpose was to fight and win. So long as we live in an imperfect world, one containing enemies of democracy, we will need a military strictly committed to combat-effectiveness. Our liberal democracy must be protected by a bodyguard of lethal warriors, organized, trained, and equipped to dominate in battle.

The need for lethality must be the measuring stick against which we evaluate the efficacy of our military. By aligning the entire military enterprise—recruiting, training, educating, equipping, and promoting—to the goal of compounding lethality, we best deter adversaries, or if conflict occurs, win at lowest cost to our troops’ lives. …

While not defining lethality explicitly, it would appear that Mattis equates it with “combat-effectiveness,” which he also does not explicitly define, but seems to mean as the ability “to dominate in battle.” It would seem that Mattis understands lethality not as the destructive quality of a weapon or weapon system, but as the performance of troops in combat.

More than once he also refers to lethality as a metric, which suggests that it can be quantified and measured, perhaps in terms of organization, training, and equipment. It is likely Mattis would object to that interpretation, however, given his hostility to Effects Based Operations (EBO), as implemented by U.S. Joint Forces Command, before he banned the concept from joint doctrine in 2008, as he related on pages 179-181 in Call Sign Chaos.

Dispersion versus Lethality

This is a follow-up post to the post discussing Trevor Dupuy’s work compared to the Army Research Laboratories (ARL) current work:

The Evolution of Weapons and Warfare?

The work by ARL produced a graph similar to this one by Trevor Dupuy, except it was used to forecast the “figure of regularity” (which I gather means firepower or lethality). But if you note there is another significant line on Trevor Dupuy’s graph, besides the weapons’ “theoretical killing capacity.” It is labeled Dispersion. Note the left side of the graph where it is labeled “Disperion: Square Meters per Man in Combat.” It also goes up as the “theoretical killing capacity” of the weapons goes up.

This is the other side of equation. For every action, there is an equal and opposite reaction to paraphrase a famous theorist. This results in this chart from Col. Dupuy:

Now….this is pretty damn significant….for as firepower, or lethality, or “theoretical killing capacity” has gone up, even geometrically…..daily casualty rates have declined. What is happening? Well, not only “for every action, there is an equal and opposite reaction,” but in fact, the reaction has outweighed the increase in firepower/lethality/killing capacity over time. This is worth thinking about. For as firepower has gone up, daily casualty rates have declined.

In fact, I did discuss this in my book War By Numbers (Chapter 13: The Effects of Dispersion on Combat). Clearly there was more to “dispersion” than just dispersion, and I tried to illustrate that with this chart:

To express it in simple English, people are dispersing, increasing engagement ranges and making more individual use of cover and concealment (page 166). Improvements in weapons, which occur on both sides, have also been counteracted by changes in deployment and defense. These changes have been more significant than the increases in lethality. See pages 166-169 of War by Numbers for a more complete explanation of this chart.

The issues related to lethality and forecasting the future of lethality gets a little complex and multifaceted.

Data Used for the ARL Paper

This is a follow-up post to this on the work being done at the Army Research Laboratory (ARL) by Dr. Alexander Kott:

The Evolution of Weapons and Warfare?

On page 9 of Dr. Kott’s paper provides the following table:

This is a sample of the data used for 8 weapons systems. He ended up using 195 weapon systems for his analysis. This is discussed in depth in his paper (referenced in his footnote 12): “Kott A. Initial datasets for explorations in long-range forecasting of military technologies. Adelphi (MD): Army Research Laboratory; 2019. 128 p. Report No.: ARL-SR-0417.” It is here:

These are all ground-based systems (no aircraft) that are either direct fire, or indirect fire systems using explosive rounds.



P.S. Now the figure of a rate of fire of 30 for the house-mounted harquebusier got my attention, and no other muzzle loading weapon has a rate of fire above 3 rounds per minute. I did discuss this with Dr. Kott. He has a note in his papers that states:

MFS048: I consider the harquebusier (see Wikipedia “Harquebusier”) of the early 17th century (taken as 1620) as light armored at 160 J of protection and with armament that is an interpolation between a light harquebus (which they often could fire only once at the beginning of the engagement and produced about 1600 J KE) and a sword/saber that produced about 100 J per hack (see data for gladius in Note MFS005). I take this intermediate effect as corresponding to about 500 J, and assign an artificial projectile mass and velocity to account for this. I assume that the maximum rate of sword blows could reach 30 per minute.

Note, his figures are based upon cyclic rate of fire, not sustained rate of fire. This will be the subject of a future post.

The Evolution of Weapons and Warfare?

Many years ago, Trevor Dupuy wrote the book The Evolution of Weapons and Warfare. One of great graphics from that book was:

This graphic either intrigued or excited the reader; or gave him serious heartburn. It was a little ambitious in a lot of people’s mind.

Well, I found something more ambitious here:

It produces this graphic:

There is a “press release” here:

The actual more detailed article is here:

This link leads to the 28-page article by Alexander Kott, chief scientist of the Army Research Laboratory (ARL). It is an interesting idea. It is an idea that I also toyed with at times, but never took the time to actually turn into a meaningful set of formulae.

I will probably have a few more comments on this work in the next couple of weeks.

What is Lethality?

Shawn Woodford did a blog post last month about Trevor Dupuy’s Definitions of Lethality:

Trevor Dupuy’s Definitions of Lethality

As he noted in a recent email to me:

I went back to look at the blog post on how TND defined lethality and it dawned on me that he actually stated it in at least two different ways:



Well, I am not sure that Trevor invested a whole lot of time in the definition or discussion of the meaning of lethality. I did work directly with him for several years and I don’t recall it ever coming up in conversation.

I think lethality is both, the destructive power of weapons and the ability to injure and kill people. It depends on the weapon and what you are shooting at. Also, depends on the measuring construct you are using. Trevor Dupuy’s models, the QJM/TNDM, were focused on estimating human losses in combat. Other combat models are built around a SSPK (Single-Shot Probability of Kill) calculation and “lethal area” calculations. This certainly includes CAA’s  COSAGE/ATCAL/CEM and the RAND/CAA’s COSAGE/ATCAL/JICM hierarchy of models. This approach is oriented toward measuring weapons system losses. Their personnel casualties are then calculated from there. I think they are both trying to measure lethality, just using slightly different metrics.

Lethality is clearly not the same as combat effectiveness. There is a lot more to combat effectiveness then what comes out of the barrel of a gun.

Cost and Lethality

While searching around the internet on discussions of lethality I found one my old forum posts from 2001. It is here:                                                                                               .

It was written in response to a question about the “cost/lethality ratio over time.” I think this post is worth repeating in its entirety, so let me post it here (with a few typos corrected):

I think this is a very important metric and one that the Institute has never been contracted to look into. To date, I have never seen any analysis that compares combat effectiveness, or lethality, to cost.

The Evolution of Weapons and Warfare was the start of a series of books that explored Trevor Dupuy’s combat models and theories of war. This book sets up the theoretical constructs behind his model. The book Numbers, Predictions and War actually discusses the first versions of the model (1977) and Understanding War (1987), which is Trevor Dupuy’s greatest book, discusses his theories of warfare. None of these address cost.

While a lot of people in the military don’t like to discuss cost, as a taxpayer, I think it is important. There are several issues here:

First, how does one measure combat effectiveness? While OLI’s (Operational Lethality Indexes) is one method, it is a scoring system for a model, and is really not intended for use as an analytical tool outside of the model. Beyond what are sometimes perjoratively refered to as “static measures” (scoring systems), there are several other more esoteric (more time consuming) ways of measuring combat effectiveness.

Second, how does one measure the synergistic effects of weapons systems? Meaning, just because weapon A is more cost effective per square meter of killing more than all other weapons, does not mean one should create an armed force of just one weapon. For example, the army of nothing but 155mm Howitzers does have severe limitations. There is a lot more that goes into weapon choice than just “bang for buck”.

Third, how does one measure the value of enabling systems? There is a lot of money spent on systems that do not shoot. This includes communications, support vehicles, engineering equipment, medical facilities, command facilities, transport, etc.

Fourth, how does one measure the value of logistic and supply support structure that backs up a military (including U.S. and forward basing)? This is also quite expensive.

Fifth, how does one measure the value and cost of personnel? The single largest cost in the U.S. defense budget is personnel. Is a $55,000 a year Captain 10% more combat effective than a $50,000 a year Captain? It includes retirement and benefits programs. Training cost is significant. What is the combat value of additional training, compared to the additional cost? The one thing our research continues to show is that the human factors are significant in military operations. Usually, the human factors are more significant than weapons or technology. If one is measuring the cost and contribution of weapons, then one also needs to measure the cost and contribution of human factors.

Sixth, what is the cost and combat value of morale building efforts? This includes housing for troops and families, recreational facilities and activities for troops and families, medical evacuation, family medical care, aid for disabled veterans and the Veterans Administration (VA), aid for widowed and orphaned families, national graveyards, Px priviledges, counciling, chaplains and ministers, USO shows, etc.

Seventh, what is the cost and combat advantage to intelligence efforts? This includes the DIA, CIA, NSA and even the DMA (Defense Mapping Agency). It also includes the various space and satillite efforts, spy planes, etc.

Eight, what is the cost and advantage of a “revolution” or further “evolution” of warfare (if there is one)?

Ninth, what is the cost and advantage of a unilateral advantage? For example, what is the combat (and political) advantage of the U.S. being able to bomb Afghanistan, Serbia/Kosovo, Iraq/Kuwait at will and relatively unmolested. This unilateral advantage is hard to measure with a simple “bang for bucks” measurment.

What you are asking is a very complex multi-faceted problem. Given sufficient time and analytical skills (and budget!!!), these issues can all be addressed to some extent. To date, I have not seen anyone try. I do not see how you are going to be able to adequently address the issues with the limited time frame, budget and page count of an Atlantic Monthly article.