All militaries must train regularly to keep their skills or learn new ones. Indeed, the best militaries of the modern age spend fortunes on training and assessing their soldiers to ensure they are not caught with their pants down should hostilities break out or power must be projected. The practice of, well, practicing is ancient and varied.
Historian Albert Nofi’s To Train the Fleet for War is an excellent look at some unique training the US Navy underwent in the Interwar period.
Background
The Interwar period, for those who are less familiar with 20th century world history, is the period between WW1 and WW2. This was a period with profound consequences in all aspects: economically, politically, technologically, etc. Developments in this era have had far-reaching implications for even our own world in the 2020s.
For the US Navy, it was an interesting time. Its purpose was largely confined to the shores of America. Within this changing world, how did the US Navy test its readiness for possibly ocean-sized or trans-oceanic warfare in as real conditions as possible?
It had the Fleet Problems.
These problems were truly free maneuvers, involving most of the US fleet(s). This was not merely a test of ship navigation, gunnery, communications, or planning, but a combination of all possible things that the Navy had to deal with in the course of its duties. Think of these problems as end-of-semester or end-of-year tests, a way of evaluating how the sailors, aviators, and officers were doing after another year of training.
Such maneuvers were not new, the navy had engaged in this since 1889. Peter Swartz notes that by 1905:
Theorizing was paced by planning: For the first time in peacetime, U.S. naval officers began to systematically plan wartime employment strategies against possible enemies first Great Britain and Spain, and later the German and Japanese empires.
Since then, however, it was never possible to have the majority of the fleet involved, as some elements were always deployed for diplomatic or war purposes to widely different parts of the world: the Caribbean, Europe, and the West Pacific.
What changed? The times.
After 1922, the US Navy was largely a stay-at-home force, turning it into a center that did nothing but innovate, learn, train, and test itself. But there were constraints as well – the Washington Treaty of 1922 had limited the number of ships it could field, and the funding allocated to the Navy was tight.
Purpose
As mentioned earlier, the purpose of the Fleet Problems was to emulate real-life conditions so that sailors and officers would be ready should hostilities break out. Another key purpose was to test the vulnerabilities in components of War Plan Orange – the plan for war with Japan.
Geography plays a big role in understanding why the Fleet Problems had the premises they did. For example, consider the premise of the very first problem, held in 1922, as summarized by Nofi:
Black (Japan) had decided to go to war with Blue (United States), using a “good will” cruise to Latin America as “cover” to position its fleet for a surprise attack on the Panama Canal. By disabling the Canal, Black would prevent the movement of the Blue Atlantic Fleet to the Pacific.
This was a major goal throughout the Interwar era, being ready to fight to keep the Panama Canal open for the US to move its fleets back and forth more easily between the two oceans. Remember, without an open canal, any fleet would have to traverse the perimeter of South America to reach the other coast i.e the Cape Horn route.
Planning
Once a problem was chosen by the Commander-in-Chief, a herculean effort would take place, typically spanning six to eight months, to get all the plans drawn up. During this time, other fleet officers would be allowed to give feedback on the plans while they were in design. If the Army was involved, it would as well.
Some issues are fairly obvious: allocations of fuel, choosing the ships that would take part, where and when the Problem would take place, the duration, etc. But a number of these questions were not trivial to solve, not at all.
Location is a good example. There are real consequences to sending your fleet to train in the areas you expect to fight. Not only are you sending a clear signal about what your thinking is, you can easily invite political backlash by appearing to be a warmonger, since why would a nation be testing its ability to fight somewhere unless they planned on beginning a war?
The solution to this problem was to replicate the desired geography elsewhere. For several problems, this meant reconstructing the Pacific within the Caribbean Sea, sometimes rotating maps to make it work.
Another problem was the forces that would be allotted to either side. A reasonable starting point would be to only use the ships that the Navy can actually afford to send, but this misses out on the value of a constructive force, a force that only exists on paper. This could be adding additional ships to a roster or treating things differently. Since the carrier Langley was not available in for Fleet Problem I, the battleships New York and Oklahoma were treated as aircraft carriers modeled on it.
The danger of such a practice is obvious, in that you can’t really tell what a fictional ship’s contribution would be. What does it mean for a battle to have a dozen more battleships, or 20 more cruisers? You might have some ability to model the impact if you know how these units operate in a given scenario, like, say, a battle line, but what about elsewhere?
Moreover, this becomes even more complicated when talking about constructive air forces because prior to mature radar technology, detecting planes required eyes on the sky. In at least one case, this failed because those on the ground weren’t informed about how one plane was a stand-in for many more, meaning they didn’t fire upon it, and it succeeded in bombing its target.
Lastly, how far can’t you go with constructive forces if you agree to use them? It takes wisdom to limit the number of fake ships, planes, and troops – someone has to recognize that simply declaring an additional 5 carriers on each side and a dozen battlewagons isn’t teaching anything unless everyone is informed and very strictly scrutinizing what happens.
These issues were known and understood at the time. Nofi gives the following quote from Vice Admiral Newton A. McCully after Fleet Problem IV, which had Black with nearly 70% constructive ships and 80% constructive aircraft:
In all exercises, constructive forces or features should be reduced to a minimum, and their functions and scope strictly defined.
Procedure
With all preparations made, executing the problem was just a matter of waiting until the right date. Earlier Problems would make moving the fleets around a scenario by itself, but later ones would just incorporate these as a phase of the overall Problem.
Of course, the officers, once assigned to their respective sides and given the “motives” for their operation, would be given free reign. They and their staffs would spend quite a bit of time doing their own planning, but changes to these plans could be made after the Problem began.
I said free reign and I meant it, because nothing was off the table, and Fleet Problem III is a perfect example. Blue (the US) faced off against Black (a “European power”, code for England) operating in the Caribbean which was to be treated as hostile waters. The Americans were therefore ordered to move down to Panama and establish a forward operating base.
Tangent: Why England? Because the US knew the Royal Navy was the premier navy of the age and potentially an ally with Japan, the nation which contested America’s claim to second-best navy and was the expected opponent in any upcoming Pacific war.
Knowing that most of Blue’s fleet was in the Pacific, an intelligence officer in the Black fleet came up with a daring plan. Leaving the fleet in a boat wearing civilian clothing, he arrived in Panama and pretended to be a journalist. Once he was in the canal zone, he obtained access to various installations, left “bombs” at a fuel depot and the controls for the locks, “cut” the telephone and cable lines, then escaped. Meanwhile, one of his officers left in the same way, but waited by the edge of the canal itself. He snuck aboard the second of Blue’s vessels coming through, then stole an ensign’s uniform. The officer then “detonated” the magazine in a suicide attack, a move that would have sunk the ship in the canal itself, rendering it unusable for the foreseeable future.
Fleet Problem VIII had another demonstration of innovative thinking, though this involved less skullduggery. The underlying premise was that tensions had risen between Blue and Orange (Japan), but not to the point of hostilities. Blue’s fleet was tasked with strengthening the garrison at Pearl Harbor (standing in for Manila) without initiating any violence. The problem lay with the S-boat submarines and repair ship Procyon, which could only reach speeds of 10.5 and 9.5 knots respectively, very slow compared to the other ships in Blue’s fleet.
The solution Blue’s commander, one Admiral Louis de Steiguer, landed upon was to have those ships towed. Like a pet on a leash or a child grasped by their parent’s hand, the larger and faster ships dragged their comrades through the waters of the Pacific. This piece of his fleet also left literally the moment the Problem began, at midnight, so that it could rendezvous with the main body departing San Francisco later that day. Orange, having assumed that Blue was constrained by the slower ships and a rising tide in San Francisco, set about scouting a predictable and defensible course, but the execution was sloppy.
All factors combined to let Blue slip entirely undetected past Orange’s fleet and reach Pearl Harbor 2 days before its deadline. The critiques afterward were scathing of Orange’s failure to analyze and plan to the extent Blue had.
One might think these ideas are trivial or even “obvious”, but I don’t think so. It can be exceedingly difficult to identify when you’ve boxed your thinking into the standards of your time, and I can easily imagine even an experienced admiral never coming across the idea that your enemy might pull their floating steel behemoths instead of running them on their own power. That does not, of course, absolve the responsibility of those on the receiving end of such tactics, contingencies for the worst case must be developed no matter what.
Keeping Score
A major issue the Navy had to deal with was how to actually score hits during the course of the Problem itself. It was hardly uncommon that the fleets on either side found each other in some manner and traded shells, torpedoes, or aircraft-carried bombs later into the era. When this happened, how were umpires to decide the number of hits?
Initially, it was just left to the umpires, nominally neutral and unbiased. In practice, there were obvious issues, especially since both sides would obviously contest how effectively they had or hadn’t been scouted or shelled. When things came to a head in 1930’s Fleet Problems X and XI, Commander-in-Chief William Pratt ordered the Naval War College to develop formal rules.
Using the 14-inch shell as a standard, they calculated how many hits a particular ship class would generate each minute and how many a ship could take before being sunk. Factors like the ship’s age, class, and type were taken into consideration. Battleships like Japan’s Mutsu and the American Maryland were allowed to take 19 and 18.6 hits respectively, while the Omaha had only 3.7 due to being a cruiser and an aged one at that.
For aircraft, this was much harder. There were histories on how ships fought and died against each other, but the empirical data on how planes performed when attacking ships was almost non-existent. Almost any data available didn’t involve attacks against large warships maneuvering with alertness, let alone battleships, which were the center of the fleets. Eventually, they settled on numbers for aircraft as well, but the sailors thought the bombs were treated as too accurate, and the airmen thought the opposite. This controversy would persist for years.
Were the estimates accurate? No, not at all. WW2 would demonstrate a depressing drop in measured accuracy by both ship guns and air attacks, especially level bombing. But arguably, that wasn’t so critical as to render the rules pointless. A more accurate simulation has value, but much can be learned by the broader context of the simulation – where a tactical gap may have occurred, or some aspect of strategic thinking that was overlooked. Insofar as the numbers resolved real-time calculations, they had some merit, I think.
Evaluation
Once a Problem was over, an extensive period of analysis would take place immediately after. This was not the calm and rational thing you might imagine. James Richardson, Commander-in-Chief from 1940 to 1941, said that “The battles of the Fleet Problems were vigorously refought from the speaker’s platforms.”
After an initial critiquing by all parties involved, extensive reports were written by all the officers involved. Then, public discussions and critiques took place in the following four days. Every piece would be examined and analyzed, from the planning and preparation to the actions each side took. Even technical and tactical discussions would take place. The Problems were, after all, a testbed for the latest ideas and technologies being developed each year. One of Chester Nimitz’s contributions in this era was the circular cruising formation, which was trialed in the very first of the Problems and adopted thereafter.
Officers were intended to attend all sessions, with the audiences correspondingly rising to the hundreds and even over a thousand for Problem XIV. The goal of these lengthy sessions was to teach the younger officers while everyone’s memory was fresh. For those men, this was a practical lesson in all the things that went into the business of the Navy and arguably strategy itself, not just their particular field or station.
This period was eventually curtailed in the 1930s, as Problems had grown too complex and massive to do the level of analysis the ones of the 20s afforded. With less ability to consider lessons learned, the Navy would lag, relatively speaking, in determining the real value or danger of a technology, tactic, or shortcoming. That said, there was still a great deal of institutional knowledge being accumulated and passed on each year.
Never Again
Fleet Problem XXI, held in 1940, was the last of its kind. Its successor was being planned but got cancelled since Europe was at war and Japan had invaded its neighbors.
After WW2’s conclusion, there were some major free maneuvers, with several taking place in 1947. November 1948 was the last time anything approaching the Fleet Problems occurred, with all three major services (Army, Navy, Air Force) working together off the coast of Florida and a Navy-Marine Corps amphibious exercise in California.
Part of the reason for this was size and makeup of the Navy itself. Nofi offers a succinct explanation.
At the time of Fleet Problem XXI in the Spring of 1940, the fleet had just six aircraft carriers, 15 battleships and about 210 other major surface warships, and some 60 submarines, plus about 175 other commissioned vessels. Despite the need to maintain substantial forces in the Atlantic, half the carriers, most of the battleships, nearly half the rest of the major surface warships, and a third of the submarines were able to take part in the problem. By the surrender of Japan in August of 1945, there were nearly 100 aircraft carriers of various types, 23 battleships, over 800 other major surface warships, and more than 200 submarines, as well as nearly 5,500 other vessels in commission, including many small combatants. Naturally, demobilization began almost immediately, and by mid-1947 the fleet again fell to approximately its pre-war strength, albeit somewhat differently composed, 22 carriers, four battleships, about 200 other major surface warships, 80 submarines, and over 500 other commissioned vessels, many of the latter new types such as command ships and amphibious warfare vessels.
The other issue was the Cold War, which demanded an entirely new strategy. Now, the US had to permanently be ready to go to war. That meant its ships would be deployed in fleets at specified hubs far from either of the American coasts. Even when at home, ships were either undergoing repair/modernization or having their sailors put through training again. The Fleet Problems, which relied on having most ships at home, were a non-starter.
Lessons Learned
What, ultimately, was the impact of the Fleet Problems?
It is impossible to answer the question without understanding that the Fleet Problems were the realization of the Interwar US Navy itself – a platform of innovation and experimentation. It transformed a navy which was, as Nofi puts it, preparing to fight a second Jutland (battleship on battleship) into one that had a better understanding of all aspects of naval combat. This includes several revolutionary technologies that would be valuable in the second World War.
A frequent criticism in the Problems, for example, had been poor communication standards, often related to complaints of weak cryptography. Constant work on this issue made the American navy preeminent on the matter by the time the period ended. There were also concerns about Japan’s faster battleships, for which solutions were found that a navy sans the Fleet Problems may not have considered other than “Go just as fast or faster!”
Nofi argues that on top of training some legendary officers like Ernest King, William Halsey, etc., the Fleet Problems helped the US Navy learn and mature on the topic of the “integrated ‘naval force’”, which was characterized by carrier battle groups and doctrine, undersea replenishment, and amphibious capability.
Still, he recognizes that there are some clear reasons why the Problems even worked in the first place.
The Navy’s strategy didn’t require most or all of its ships to be deployed and had only one probable enemy in Japan.
The fundamental conflicts hadn’t changed with new technologies, it was still a “force- on-force industrial-age model of warfare.”
The officers were all part of the same “Big Gun” community as well, though naval aviation proponents would come from this group.
Personnel churn was minimal, allowing for a very professional force to develop.
Ultimately, the Fleet Problems represent what one imagines a competent military service to do – constantly train, learn, and experiment for the next war. Nofi’s in-depth treatment of the Fleet Problems shines a spotlight on an institution working as close to the ideal as I can ever imagine.
Sources
Albert Nofi, To Train the Fleet for War: The U.S. Navy Fleet Problems, 1923-1940. Goodreads
Peter Swartz, Sea Changes: Transforming U.S. Navy Deployment Strategy, 1775–2002. Center for Naval Analyses
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