13: The End of the Naval Treaty


In this episode we will discuss the final collapse of the Treaty, which the Royal Navy had started planning for years in advance. Then we will look at some of the concrete plans and actions that the Royal Navy would start the moment that the Japanese withdrew from the treaty restrictions. We will only talk about the modernization efforts that resulted from these plans today, before diving into the planning and construction of the King George V class next episode, at which point we will look at all of the other British pre-war battleship designs.

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Hello everyone and welcome to History of the Second World War Members Episode 13 - The Royal Navy Part 3 - The End of the Naval Treaty. Last episode we discussed some of the problems faced by the Royal Navy in the early and mid 1930s as the threats that they faced in Europe continued to grow. The entire treaty structure was built around the fact that the British did not have to greatly worry about what was happening in Europe during the 1920s, but they would decisively change during the 1930s. This made the British far less likely to support just a straight continuation of the agreements made both in 1921 and 1930, with even the 5:5:3 ratio which had taken so much of time to get to an agreement on being seen as the bare minimum, and perhaps unacceptable. In this episode we will discuss the final collapse of the Treaty, which the Royal Navy had started planning for years in advance. Then we will look at some of the concrete plans and actions that the Royal Navy would start the moment that the Japanese withdrew from the treaty restrictions. We will only talk about the modernization efforts that resulted from these plans today, before diving into the planning and construction of the King George V class next episode, at which point we will look at all of the other British pre-war battleship designs. In retrospect the planning and discussions around the end of the treaty would be incredibly important to the later British war efforts. They of course did not know it in 1936, but very few of the ships that would be started in 1937 and later would actually be complete in September 1939, and very few more capital ships would be completed during the war. This made the choices made in 1936 around how to spend the budget, which ships to modernize, and the design decisions around capital ships some of the most important that the Royal Navy would make during the interwar years, even if they did not fully understand this at the time.

One thing I also wanted to mention at the start of this episode was the state of the Royal Navy at this point in time, just looking at numbers. It cna be tempting, and I have certainly fallen into this a bit myself, to paint the Royal Navy as some sort of huge underdog, or a Navy that was behind the times during the 1930s. However, by the mid-30s, and really all the way to the start of the war, the Royal Navy was incredibly strong, even in comparison to every other navy in the world. Before other navies began their final pre-war ships the Royal Navy had three of the strongest naval vessels afloat in the Nelson, Rodney, and Hood. All three were certainly showing their age, but so was every other capital ship around the world that had been allowed as part of the Washington treaty. This is easy to forget because all three of the ships would not receive pre-war modernizations, even though they were all planned to receive them starting in 1940. They did not compare well to the new ships of the late 1930s, but that is an unfair comparison. The Royal Navy was also roughly at parity with other navies for aircraft carriers, with the Ark Royal being the first purpose built Royal Navy carrier, which was launched just a year after the American carrier Yorktown. The Royal Navy had spent, and would continue to spend, a lot of money on destroyers and cruisers, which would give them one of the largest and youngest fleets of small ships in the world when the war began. Even with all of these strengths, the Royal Navy is often painted with a very negative brush during the last 5 years of peace, and as I mentioned I have fallen into that a bit as well. There are two reasons for this, the first was that they had many responsibilities all over the world, which had a tendency to spread the available strength very thin, and forced them into confrontation with multiple other navies simultaneously. They also end up getting compared to the American and Japanese navies of 1941, both of which had over 2 years of relative peace to continue to build their navies, while all major construction for the Royal Navy essentially ended in 1939 and early 1940 while resources were needed elsewhere. I don’t necessarily have a grand point by bringing this up, but I thought it was good to reset expectations and mindset before we continue. With that out of the way, lets talk about why the Japanese were so unhappy with the treaty system in the mid 1930s, and why they wanted out.

While the treaty would expire in 1936, it was actually a dead agreement in 1934. This was because in May 1934 the Japanese would announce their belief that the agreements that had been made in London in 1930 required massive revision, specifically related to Japan being forced into a second rate position. The Japanese would also insist that any discussions that they had with other powers would only involve Naval topics, which clearly signaled that they were not open to discussing events in China or including discussions of those events as part of any naval talks. While the Japanese were pushing for parity the overall plan for the British delegation was to push for qualitative changes that was the origin of the push for 25,000 tons and 12 inch guns. From the British perspective any revision of the capital ship ratios was completely off the take and would not even be discussed.

The British and Americans would get together in June 1934, before involving the Japanese in further discussions. During this meeting about their respective plans for the conference, while they disagreed on many specific details, they would both agree that the most important piece of any future discussions was that the ratio provided to the Japanese should not be revised. They both agreed to not make any agreements with the Japanese about the ratio without the other nation being involved. At the same time the British and Japanese would also be having discussions, particularly around timing, with the British wanting the begin the official conference in January 1935, while the Japanese wanted to wait until later in the year. All kinds of other unilateral discussions would also occur during this period. With the British meeting with the French, in which the French would emphasize how important submarines were to their naval plans, while also making it clear that they were likely to agree with many changes to the agreements as long as their parity was maintained with the Italians. The Italians would then also meet and announce to the British that they were quite set on building two new 35,000 ton battleships, which were allowed to them under the existing naval agreements. The French then insisted that they would also build two such ships to match up with the Italians. These building plans basically ended any British hopes of smaller ship limits, nobody was going to want to build smaller ships after new 35,000 ton ships started to be laid down. However, there was overall less insistence on any ratio changes among European powers, with the French and Italians not really pushing for ratio changes as long as the other was not allowed more building than they were.

These views would clash with the Japanese insistence on change, and during discussions late in 1934 the Japanese would not budge from this position. This caused deadlock at the conference, with the British only wanting to discuss qualitative limitation changes, so smaller capital ships, the Japanese only wanting to discuss quantitative changes, and the Americans not really wanting to push forward with either set of changes. The Japanese were also not the only nation causing problems. The British would not really help themselves at the conference with the signing of the Anglo-German naval treaty in 1935, which caused other nations, and especially France and Italy, to be very displeased that the British would sign something without informing them of the changes. Eventually Japan would inform the other nations that it would officially refuse to sign any further extension of the treaties, which meant that the agreements between Japan and the other nations would end after 1936. To be absolutely fair to the Japanese, they did all of this completely by the book, and they exited the treaty in precisely the way that they could and should which was outlined in the Washington Naval Treaty. Even with their stated refusal, there would still be a London Naval Conference which would begin in December 1935. Most of the major naval powers were involved, and Japan even sent a delegation if only to keep tabs on what was happening. There were also discussions of including the Germans and Soviet Union to make up for the withdrawal of the Japanese. The French effectively vetoed both of these additional, just straight up refusing to have discussions with German representatives, as they saw such discussions as a tacit acceptance of Versailles revisionism. They also rejected the inclusion of the Soviet Union out of concern that it would antagonize the Japanese. The eventual agreement in London on March 25, 1936 would still include some qualitative limits, with 35,000 tons and 14 inch guns for battleships being the headline items.

But critically, it also included an escalator clause that allowed for the usage of 16 inch guns if one of the Washington Naval Treaty signatories refused to sign the new agreement, which was essentially assured that the Japanese were not interested. This escalator clause was insisted on by the Americans, who went into the conference strongly preferring a 16" gun limitation. When it was clear that many other nations were at least accepting, or even preferred the 14 inch limit, the Americans agreed to it with the addition of the clause. It was a near certainly that the Japanese would not sign the agreement, which meant that it was very likely that the escalator clause would be activated. This was an interesting moment where the design thoughts from the American and Royal Navies came into conflict. The two navies had very different designs for a 35,000 ton battleship, with the British strongly preferring greater armor. This meant that they did not actually believe that the best 35,000 ton ship could even mount 16 inch guns, and in fact 16 inch guns should only be included on ships of at least 40,000 tons. The Americans put less emphasis on armor and therefore believed that they could build the ship that they wanted, with 16 inch guns, within a 35,000 ton limit. While the outcome of the conference was a failure for the Royal Navy, at least when it came to getting what they wanted, especially around qualitative limits, at the very least it was a perfect example of the growing Anglo-American cooperation. The overall feelings in 1930 were relatively antagonistic between the two navies, but by 1936 all of the discussions and decisions that had been made before and during the conference between the two navies had brought them closer together. This was a very positive development, as it would turn out.

As we discussed on an earlier episode early in 1936 the Royal Navy would fully re-evaluate the plans that it had for a new building program which seemed destine dto start in the near future. With the clear disintegration of the treaty arrangements, and most importantly it becoming less and less likely that the British plans for displacement reductions would gain acceptance, the plans for the 35,000 ton designs would begin to be refined. At this time there were also discussions around what it would take to rapidly accelerate those building plans should it be required. This would result in the Supplementary Estimate of 1936, which would be based around the idea of bringing three battleships that had originally been planned for 1937 to instead be laid down in late 1936. Recruiting was also another critical aspect of these expension programs. It was very clear that if the Navy wanted to grow as much as it was planning, the number of men in the service would have to begin to increase quite quickly. This meant an increase of almost 30% up to at least 130,000 by 1940. This was no small amount of change, especially financially, and during the 1920s and early 30s there were constantly trying to make even small reductions to the overall manpower of the Navy. All of these acceleration of and growth discussions only grew more urgent as many other nations began to publicly announce their planning building programs, which was required under the Washington Naval Treaty system, and the Anglo-German treaty. During 1936 the Germans would start construction of another battleship, which would eventually be the Tirpitz. The French had started the ships that would eventually be the Richelieu and Jean Bart, Italy would join the others in constructing a whole host of smaller cruisers, destroyers, and submarines. There were reports that the Russians were also planning on two 16 inch armed battleships as well. Meanwhile, in America the First Vinson Act had been started with the goal of building up the American Navy to its treaty authorized limit, which during the 1930s it had not been keeping up with. During 1936 the Americans would only start on a number of smaller ships, destroyers, and submarines, but in early 1937 there would be discussions about really boosting that construction rate. Japan would also start seeing the fruits of their first and second replenishment programs which had been started during the previous years, designed to massively expand all of their armed forces including the navy. All of these new building programs would put the Royal Navy in a bit of a bind, because the conclusion of their new design program had been that a 14 inch gun was the way to go for their next set of battleships. As every other nation started building 15 and 16 inch armed ships the Royal Navy would decide to stick with their previous decision. However, this was driven just as much by fears of delay than any other reason. Admiral Henderson, at the time the controller of the navy, believed that a shift to 15 inch guns would require a roughly 18 months delay and the ship would have to be made significantly larger if they wanted to go all the way up to 16 inch guns. With these issues in mind the previous decision for 14 inch guns would be maintained, with the understanding that it might need to changed after 1937.

Along with the new construction that was being planned modernization efforts were also critical. The idea of large, and costly, modernization of pre-treaty capital ships was an idea that really started to gain traction after 1930. It was in that treaty, with the extension of the ban on capital ship construction out to 1937, that many navies started to seriously consider some level of updates on capital ships that they had been allowed to keep under the Washington treaty. Many of those ships were pre-WW1 vintage, or at the very least had been completed during or immediately after the war, and by the time that the treaty was due to expire they would be over 20 years old. This was very problematic when it came time to think about the prospects of these ships in the face of the new construction that was happening around the world. The British were actually quite late to the game when it came to modernization efforts. By 1933 the United States had already gone through a modernization cycle on many of its Washington allowed capital ships, and both the United States and Japan would go on to spend quite a bit more on those efforts as the years continued. The Royal Navy was a bit slower on the uptake, primarily for budgetary reasons, with each modernization effort planned to cost around 3 million pounds. The overall goal of these efforts was to extend the life of the ships into the 1940s, at which point it was planned that they would be fully replaced with new construction. The plan as of 1931 was to have the Royal Sovereigns all replaced by 1942, the Queen Elizabeths by 1944, the Repulse and Renown by 1945, and the Hood, Rodney, and Nelson between 46 and 48. This meant that the modernization efforts were only really designed to extend the life of the ships by 5 to 7 years, and the Admiralty would go to great pains to make it clear, and then to reemphasize many times, that such modernization efforts should not be seen as a substitute for new warship construction, they were instead simply to bridge the gap until enough new ships could be completed. During the mid 1920s many of the British capital ships that had survived Washington had gone through the small modernization program. At that time the decision had been made that, with the funds available at the time, it was more important to bolster the torpedo protection present on the ships, rather than spend the money on defense against air attack. Or as the Admiralty sub-committee on the matter would say ‘at present underwater protection is more important than deck protection, though the position in the future may be reversed if there is any great development in bomb dropping from aeroplanes’. This would be the origin of many of the torpedo bulges which would be so noticeable on so many ships from this time period. When it came time for the 1930s modernizations, the threat from the air would be re-evaluated, and was judged to be far more concerning and worth a greater investment into both anti-aircraft weaponry and armor against air attacks. The armament additions had actually been ongoing since around 1933, as weapons became available, because it was far easier to just add on some anti-aircraft weapons, and it had been done anytime ships were brought into port for any major maintenance. This included not just more anti-aircraft guns but also new and more capable high angle fire directors which would make all of the anti-aircraft guns more efficient. This process, of adding additional AA guns and capabilities would be accelerated after 1936, as the treat of war in Europe began to increase, it would also not really end until the end of the Second World War, and if you read about any capital ships going into port during the war they almost always seem to exit with either more or newer anti-aircraft guns. Armor to protect from air attacks was a bit more challenging to just increase on an ad-hoc basis. It was quite a bit more difficult to just throw some additional armor on, and so the large 1930s modernization efforts were a perfect time to tackle the problem. This would also provide additional protection from plunging gun fire, a problem that had just been growing over the decades as possible engagement ranges continued to increase. Armor was also heavy, it and it was only through the costly and time consuming re-engining efforts that were done to the ships, which essentially required an entire new set of engines, boilers, and other machinery, that the weight for additional armor could be found. But there were limits on how much new armor could be added, and so they would have to really consider what the threat was. This is where the timing of the refits, and their expected lifespan, comes into play. When the modernizations were being planned, which was the early 1930s, the threat profile from aircraft was quite different. For example, a 550 pound bomb was pretty much the maximum that could be carried by carrier aircraft. It was impossible to know how quickly carrier aircraft would accelerate in terms of capabilities in the late 1930s and early 40s, but also for many of the modernized ships the plan was to retire them by the mid 1940s anyway, which meant there did not need to be as much concern about the growth of the aerial threat.

Warspite would be the first ship to be given the modernization improvements, which we dove into in some detail in the Warspite special. The re-engining and replacement of so much machinery resulted in massive weight savings, around 1290 tons, and it also made that macherinery smaller and far more efficient, resulting in more power while consuming less fuel. This combination of factors allowed the Warspite’s range to increase from 8400 nautical miles to 14300 nautical miles. New turrets were also fitted,which allowed the guns to be fired at a higher angle, increasing the maximum engagement ranges of the ship. This turret change was directly necessitated by the new ships that were being built by other nations, which could fire their guns at higher angles than the oldest British ships, which had a 20 degree maximum elevation, which were increased to 30 degrees during modernization. All told the Warspite would take 3 years, and it would cost 3 million pounds, and when it was done the Queen Elizabeth was started, with the Valiant planned as the third. At that point the plan was to work on the Hood. After these large modernizations were done, the plans were a bit different, and while it was recognized that additional ships required modernization efforts it was unclear as to how extensive they would be. As their date of retirement approached the rest of the Queen Elizabeths, Renown, Repulse, Nelson, and Rodney were in a bit of a different position, and so their modernization efforts, to whatever extent they would have been, would have been precisely determined in later years. Of course those later years never came, because the war started, and modernization efforts were ended soon after the declaration of war, with the Hood never being taken in hand if only because it, along with every other ship, had a job to do.