Briefing - An Overlooked Angle on the Naval Arms Limitation Treaties
At the end of World War I only two navies were stronger, both in absolute and in relative terms, than when the war had begun, the U.S. and the Japanese. The German and Russian navies had been virtually eliminated, the one by defeat and the other by revolution, while the French and Italian fleets had fallen decisively into the second rank by reason of poverty. To be sure the Royal Navy was still the largest in the world, but its margin of superiority over its closest rivals had narrowed considerably.
|Projected Capital Ship Balance, 1926|
|Note: The table only includes dreadnought battleships and battle-cruisers. The figure for 1926 is projected based on existing building plans.|
Since the ‘firt line’ life of a battleship in those days was only about ten years, by 1926 anything built prior to the outbreak of World War I would have been obsolete, while anything completed during the war would have been approaching obsolescence. This mean that by 1926 the Royal Navy would have had only 18 modern battleships, some of them nearing obsolescence, since they had been completed between during the war, while the Imperial Navy would have had 24 and the U.S. Navy 27, most relatively more modern than Britain’s. Obviously, to maintain its position as the primary maritime power, Britain would have had to build more ships. But then the U.S. and the Japanese would have responded by building more of their own. So by the mid-1920s a money battleship building contest would have developed among the three power, consuming enormous amounts of money. As Japan would have run out of money first, its only options would then have been to abandon any pretense of being a first class naval power or go to war.
To avert the incipient arms race, and the possible threat of war, in 1921 the British suggested a naval arms limitation conference, in compliance with the disarmament provisions of the Treaty of Versailles The conference met in Washington in 12 November of 1921, with delegates from the U.S., Britain, Japan, France, and Italy. On the very first day Secretary of State Charles Evan Hughes dropped a bombshell. Subtly observing that the U.S. had the economic wherewithal to out build both its rivals, Hughes announced that America would be willing to scrap a significant portion of its existing fleet and of vessels still under construction, if the other powers would do the same and agree to limitations on the size of their fleets. The offer was greeted "with almost indecent haste," as one naval historian put it. This led to an agreement to reduce the respective fleets in a proportional fashion, while imposing limits on the replacement rate and size of future capital ships and the newly invented aircraft carriers, an agreement that was extended to other classes of warship by the London Conference of 1930-1931.
The treaties led to the scrapping a lot of obsolete vessels; the U.S. got rid of 28 pre-dreadnoughts and first generation dreadnoughts, the Japanese 13, and the British 30, after having already disposed of about two dozen even before the treaty was signed. The treaties permitted the three principal navies to complete a couple of newer ships, to preserve “balance,” and allowed the U.S. and Japan to complete two incomplete ships as aircraft carriers, and France one. The key to the treaty was the ratio of capital ships it imposed among the naval powers.
The treaty established a 5:5:3:1¾:1¾ between Britain, the U.S., Japan, France, and Italy. That is, each for five battleships the U.S. and Britain had, Japan could have three and so forth, expressed in terms of tonnage, though with numerical limits imposed, since ships to be retained or completed were identified by name. That meant that under the terms of the 1922 agreement Britain would have 20 capital ships, the U.S. 18, and Japan 10, with France and Italy relegated to the minor leagues, and will henceforth be omitted. When the 1930 agreement was concluded, the number of ships was further reduced, so that Britain and the U.S. ended up with 15 each, and Japan with 9,
Now this would seem an equitable arrangement, balancing the fleets. But in fact, a very good case can be made that it left the U.S. Navy as the most powerful of the three.
The supreme arbiter of sea power prior to World War II was the big gun battleship. And the treaties left the U.S. with more big guns than anyone else.
|Guns Under the 1922 Washington Treaty|
|U.S. (18)||Brit. (20)||Jap. (10)|
|Note: Figure in parentheses is the number of capital ships (battleships and battlecruisers) owned by each navy.|
METAL is the combined weight of all projectiles if each gun fired just one armor piercing round, expressed in tons.
So under the terms of the 1922 treaty, although the U.S. Navy had fewer capital ships than the Royal Navy, it had about 8-percent more heavy guns than the British Fleet. And while , the U.S. Navy had 80-percent more battleships than did the Imperial Navy, it had nearly 90-percent more heavy guns. Of course, about a quarter of the American tubes were 12-inch caliber, thus reducing the U.S. Navy’s “weight of metal” (i.e., the weight of projectiles). On the basis of weight of metal, the U.S.N.’s firepower was barely 95-percent that of the Royal Navy, but nearly 175-percent that of the Imperial Navy. The American situation became even better after the implementation of the London treaty.
|Guns Under the 1930 London Treaty|
|U.S. (15)||Brit. (15)||Jap. (9) |
|12"|| 12|| - || - |
|14" || 124|| - || 72 |
|15" || -|| 100|| - |
|16" || 24|| 18 || 16 |
|TOTAL || 160 || 118|| 88 |
|METAL|| 123.5|| 112.2|| 71.5 |
The scrapping or “demilitarizing” of several more ships under the terms of the 1930 treaty, left the U.S. with the same number of capital ships as the Royal Navy owned, but with over 35-percent more heavy guns. On the other hand, the number of American battleships was now only two-thirds greater than Japan’s, and its number of heavy guns only about 80 percent more. In terms of weight of metal, by the early 1930s the U.S.N.’s firepower was 110-percent that of the Royal Navy, though “only” about 173-percent that of the Imperial Navy. Arguably the U.S. Navy had lost ground to the Imperial Navy, but not by much.
So although the naval arms limitation treaties concluded in Washington and London in 1922 and 1931 are portrayed by American navalists as having severely crippled the United States Navy – a line still parroted today by the Navy League – in fact the treaties can be said to have made the U.S. Navy the most powerful in the world.