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Measuring and Modelling Naval Presence

15 Dec 23

106 pages

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Commander Andrew Livsey

Many naval officers will instinctively be sure that the presence of naval forces in a region makes a difference. The Royal Navy certainly believes so, as the long-standing deployment of forces to the Gulf and the careful discussions about where the carriers are to be sent attests. But how important is this presence, and how do we judge its importance against the other demands on the time of scarce assets?

In Measuring and Modelling Naval Presence, Captain Jerry Hendrix USN (Rtd) PhD makes a valiant and original effort to give an answer. He starts with a useful review of the literature. Among other points this brings out that presence has disadvantages in terms of training and equipment readiness. An alternative is to keep a fleet closer to home, focused on preparing for war, and achieving deterrence through capability rather than proximity. Hendrix then reports the result of interviews with six retired US Component Commanders, officers who have commanded significant forces across vast regions, working to tie together military movements with diplomatic results. All agree on the importance of presence, and they make useful points about the messaging value of flexing forces between regions and the limited usefulness of “virtual presence”, for example the latent capability to launch a cyber-attack. Hendrix also discusses how the audience’s assessment of the broader capability of a nation and its willingness to act create a ‘national lens’ through which its naval movements are perceived. Throughout Hendrix’s practical experience of maritime operations shines through, for example in his discussion of the ‘death spiral’ of an overworked force, as an extension in refit time for one unit can mean that maintenance on other units is postponed, leading to their refits taking longer in turn. Both the USN and RN have suffered from this problem.

A discussion of different models and assigning numbers for the utility of different platforms then builds towards the heart of the paper, the presentation of an equation which can allow the relative presence influence of two states in a particular region to be assessed. It does so incorporating current forces, geography and wider factors in an impressive manner. This is the kind of intellectual product that the USN does better than anyone else, in part due to their ability to develop naval officers who are also experienced as operational analysts. There are shades here of the late Captain Wayne Hughes USN’s famed salvo equations.

Is the model a useful addition to existing thought? Yes, but with caveats. It is useful because mathematical models are a good way to force one to examine the inputs and quantify factors such as range and reliability rather than just listing things that are important. It also makes one examine how they interact. One could use the equations to judge which side had an advantage in a particular situation, something that has not been possible before. This can be used by decision makers in a much more practical way than most texts. There is also value if someone disagrees with some of Hendrix’s suggestions, for their specific nature helps to focus the discussion.

The first caveat is that Hendrix doesn’t test his model against real world events as Stephen Biddle, for example, does in his book Military Power. Ideally there would be a series of worked examples, with the presence factor of each side stated and related to the real world historic diplomatic outcome. Without these we might instinctively think that Hendrix has come up with a well-argued set of factors, but there is no real proof that they work in practice. Relatedly, the paper still doesn’t answer the question of how useful presence is overall. If one has twice the level of presence in a region as an adversary, what will that mean?

There are also some minor niggles. The same content might be expressed more succinctly, there is not enough discussion of the limitations of what is being done, the inputs are almost entirely US based and there are better lists of presence events than given in the annex, such as in Captain Kevin Rowlands RN’s Naval Diplomacy in the 21st Century. There is also a shift from the main unit of reference being the individual destroyer to the carrier, which is not completely explained, and the conclusion could summarise the points more comprehensively.

But focusing on the caveats and niggles would be to miss the point. Unlike most recent writers on the subject, this paper takes the study of the value of naval presence in an interesting new direction rather just building on and adapting James Cables’ Gunboat Diplomacy from 1971. The inputs from the experienced officers give some insight and the equation offers hope of putting practical values on issues that have hitherto been discussed too vaguely. Could aspects be done better? Possibly, but its success lies in that one wants more. This is not the final word on the subject, but I expect and hope that Hendrix and others take his ideas further. Hendrix’ article is recommended reading if you want to understand how this part of the sea power discussion is developing.