Washington Naval Treaty

Washington Naval Treaty

The Washington Naval Treaty, also known as the Five-Power Treaty, limited the naval armaments of its five signatories: the United States of America, the British Empire, the Empire of Japan, the French Third Republic, and the Kingdom of Italy. The treaty was agreed at the Washington Naval Conference, which was held in Washington, D.C. from November 1921 to February 1922, and was signed by representatives of the treaty nations on 6 February 1922.

The U.S. Senate ratified the treaty on 29 March 1922; President Warren G. Harding signed it on 9 June 1923; the ratifications were deposited with the U.S. federal government on 17 August 1923, and were proclaimed on 21 August 1923.

The terms of the treaty were modified by the London Naval Treaty of 1930 and the Second London Naval Treaty of 1936. By the time of the latter, Japan had declared it would no longer abide by the terms of the treaty and Italy was secretly ignoring it. Germany was never affected by the Washington or London treaties; its naval construction was controlled under the Treaty of Versailles, the peace treaty that ended World War I.


In the aftermath of World War I the British Empire had the world's largest and most powerful navy, followed closely by the United States and more distantly by Japan. All three embarked upon large programs of new capital ships (battleships and battlecruisers). In 1920, the United States had declared an aim to produce a navy "second to none", and had already laid down keels for five battleships and four battlecruisers. Japan was at the start of an 8:8 program (eight battleships and eight battlecruisers). In early 1921 the British finalized the design and ordered four very large battlecruisers (G3 battlecruiser) with plans for four matching battleships (N3 battleship) to follow. This burst of capital ship construction kindled fears of a new naval arms race, similar to the Anglo-German Dreadnought race leading up to World War I.

At the time, the United States' economic power was considerably greater than its potential rivals'. Its Gross Domestic Product was approximately three times larger than the United Kingdom's (note that here the terms United Kingdom and British Empire are not synonymous) and six times larger than Japan's. While the United States had the wherewithal to outbuild the other maritime powers, rising isolationism meant that domestic political support for such an ambitious program was lacking. The Japanese and British Empires were linked by the Anglo-Japanese Alliance which included mutual defense. The prospect of a naval limitation treaty offered the American government a chance to appeal to isolationist sentiment at home while offering the Japanese and British governments a more favorable balance of power compared to the United States than they could have achieved on the building ways.

Cryptanalytic influences on the treaty

What was unknown to the participants in the Conference was that the American Black Chamber in New York City, under Herbert Yardley, was spying on the delegations' communications to and from their home capitals. In particular, Japanese communications were thoroughly penetrated, and American negotiators were able to get the minimum possible deal the Japanese had indicated they would accept, and below which they would leave the Conference. As this ratio value was unpopular with much of the Imperial Japanese Navy, and with the increasingly active and important ultranationalist groups, the value the Japanese Government accepted was the cause of much suspicion and accusation among Japanese between politicians and Naval officers.


After specifying some exceptions for ships in current use and under construction, the treaty limited the total capital ship tonnage of each of the signatories to the values tabulated at right. In addition, no single ship could exceed 35,000 tons (35,560 t), ["The word "ton" in the . . . Treaty, except in the expression "metric tons", shall be understood to mean the ton of 2240 pounds (1016 kilos)." [http://en.wikisource.org/wiki/Washington_Naval_Treaty%2C_1922#STANDARD_DISPLACEMENT "Treaty", Section II, Part IV, Definitions, "Standard Displacement"] .] and no ship could carry a gun in excess of 16 inches. (406 mm).

The "standard tonnage" was defined in the treaty to exclude fuel (and boiler water) because Britain argued that their global activities demanded higher fuel loads than other nations and they should not be penalized. [ "the ship complete, fully manned, engined, and equipped ready for sea, including all armament and ammunition, equipment, outfit, provisions and fresh water for crew, miscellaneous stores and implements of every description that are intended to be carried in war, but without fuel or reserve feed water on board." In both Washington and London treaties]

Aircraft carriers were addressed specifically by the treaty. In addition to total tonnage limits, rules regarding maximum vessel size were imposed. Only two carriers per nation could exceed 27,000 tons (27,400 t), and those two were limited to 33,000 tons (33,500 t) each - this exception was in fact made to allow the reuse as carriers of certain battlecruisers being built, and gave birth to the USS "Lexington" and the "Akagi". The number of large guns carried by an aircraft carrier was sharply limited—it was not legal to put a small aircraft on a battleship and call it an aircraft carrier.

As to fortifications and naval bases, the United States, the British Empire, and Japan agreed to maintain the status quo at the time of the signing. No new fortifications or naval bases could be established, and existing bases and defenses could not be improved in the territories and possessions specified. In general, the specified areas allowed construction on the main coasts of the countries, but not on smaller island territories. For example, the United States could build on Hawaii and the Alaskan mainland, but not on the Aleutian Islands. The various navies of the British Empire — considered under the treaty as one entity — were treated similarly and the facilities of the Royal Australian Navy (which had to give up the battlecruiser HMAS "Australia") and the New Zealand Division of the Royal Navy could be built up by their respective governments, but not the base of Hong Kong. Japan could build on the home islands, but not Formosa.

Treaty members were allowed to replace or build ships within the terms of the Treaty but any build or replacement had to be directly communicated to the other Treaty signatories.

On 29 December 1934, the Japanese government gave formal notice that it intended to terminate the treaty. Its provisions remained in force until the end of 1936, and it was not renewed.


In Europe, the Treaty changed planned building programs for most of the signatories. The British gave up their planned N3 battleships and G3 battlecruisers. Almost all of the forces built new designs in the new "heavy cruiser" class, but at the same time few new battleships were built. Instead, extensive conversions were made to existing battleships and battlecruisers, resulting in fleets in World War II that consisted primarily of ships laid-down before World War I. The United States built no new battleships until the keel of "North Carolina" was laid in October 1937 — a span of nearly 20 years.

A number of attempts were made to build new battleship designs within the Treaty limitations. The need to increase armor and firepower while keeping weight under the Washington limit resulted in experimental new designs like the British "Nelson"-class (based in part on the G3 design) and the French "Richelieu".

In general ship effectiveness is related to speed, armor and armament. Weight is related to ship length which permits higher speeds. Each nation used a different approach to circumvent the treaties. The US used high strength boilers for higher speeds in a smaller ship. Germany used high strength steels for better armor and lower weight (although this was in response to the Treaty of Versailles, not the Washington Naval Treaty). Britain designed ships that could have armor added after a war began, and in the case of "HMS Rodney" and "HMS Nelson" enhanced their armour by using boiler feed water tanks as part of the protective scheme. Italy simply lied about the tonnage of their ships. Japan withdrew from the treaty in 1936, and continued the building program that they had previously begun, to include placing 18.1 inch (460 mm) guns on battleship "Yamato".

The majority of European nations were not concerned with military operations far from land, and therefore there was little interest in aircraft carrier construction. The Germans, French and Italians did not bother with aircraft carriers until World War II was clearly looming, at which point all of them started construction in small numbers. The Royal Navy, tasked with long-range operations the world over, clearly needed carriers and so continued construction. Between 1920 (prior to the treaty) and the start of World War II the British built six new carriers, all various one-off designs. The US had six carriers at the start of the war, not including the old CV-1, "Langley", as she had been converted to a seaplane carrier (AV-3) in 1936 to allow for the completion of "Wasp". After the Washington Treaty terminated, the US laid down six new carriers, starting with "Hornet" (a repeat "Yorktown") and "Essex" (the first of a new class). Japan converted incomplete battleship "Kaga" and battlecruiser "Akagi" to aircraft carriers to conform to Washington Naval Treaty. These conversions provided much needed experience and helped to build future classes of aircraft carriers. Japan had ten carriers at the start of the war.

The French were not pleased with the treaty. They had argued that they should be allowed a larger fleet than Italy, since France had to maintain a fleet in both the Atlantic and the Mediterranean, but the Italians had to be concerned only with the Mediterranean. This would obviously imply that the Italian presence in the Mediterranean would be stronger than the French. Nevertheless, they signed the treaty, partially reassured by their alliance with the British.

The effects of the Treaty on the United States could not have been more different. The Treaty, coupled with the attack on Pearl Harbor on December 7 1941 was a major cause of the United States Navy's conversion from a battleship fleet to a carrier-based force.Fact|date=March 2008

The United States was over the limits in capital ships when the treaty was ratified, and had to decommission or disarm several older vessels in order to comply. However, the only aircraft carrier in the US fleet before the treaty was signed was USS "Langley" (11,500 tons, 11,700 t), a converted collier. Not only did carriers have separate limits, but as an experimental vessel, "Langley" did not count against the tonnage restrictions. The US Navy thus had a free rein to build carriers.

In the 1920s the Department of the Navy had a low opinion of the concept of naval aviation despite (or perhaps because of) Billy Mitchell's 1921 success in using US Army Air Service bombers to sink the German battleship "Ostfriesland". However, to comply with the treaty, two battlecruisers of the "Lexington" class still under construction, USS "Lexington" (43,500 tons, 44,200 t) and USS "Saratoga"(43,500 tons, 44,200 t), had to be disposed of. They were converted into carriers USS "Lexington" (33,000 tons, 33,500 t) and USS "Saratoga" (33,000 tons, 33,500 t), although that choice was only slightly preferred over scrapping. However they were also equipped with eight 8-inch guns, the maximum number of that caliber allowed by the treaty for aircraft carriers bigger than 27,000 tons. The treaty allowed these ships to displace 33,000 tons, and have an additional 3,000 tons added for deck and underwater protection; [citeweb
title = "Treaty", CHAPTER II.-RULES RELATING TO THE EXECUTION OF THE TREATY- DEFINITION OF TERMS, Part 3- Replacement, Section 1, RULES FOR REPLACEMENT, subsection (d) | url = http://en.wikisource.org/wiki/Washington_Naval_Treaty%2C_1922#SECTION_I.-RULES_FOR_REPLACEMENT
] hence a final 36,000 ton standard displacement figure. [cite journal
last = MacDonald
first = Scot
title = Langley, Lex and Sara
journal = Naval Aviation News
pages = 19–20
date= May 1962
url = http://www.history.navy.mil/download/car-3.pdf
accessdate = 2007-12-02
] They were subject to a great deal of creative accounting as to these figures, and both were far closer to 40,000 tons at the time they were commissioned.Fact|date=December 2007

In 1931, the United States was still well under the treaty's limit on carriers. USS "Ranger" (14,500 tons, 14,700 t) was the first US carrier designed as such — no other class of capital ship could be built — and the Navy began incorporating the lessons from those first four carriers into the design of two more. In 1933, Congress passed Franklin Roosevelt's "New Deal" package of legislation, which included nearly $40 million for the two new carriers: "Yorktown" (19,800 tons, 20,100 t) and "Enterprise" (19,800 tons, 20,100 t). Still bound by the 135,000 ton (137,000 t) limit, the keel of the final US pre-war Treaty carrier "Wasp" (14,700 tons, 14,900 t) was laid down on April 1, 1936. The US Carrier Fleet now totaled 135,000 tons (137,000 t), nominally, and there it remained until the treaty was terminated by Japan in 1936. As with their predecessors, the two "Yorktown"s and "Wasp" were subject to a great deal of creative accounting; their actual displacements were closer to 25,000 and 20,000 tons respectively.Fact|date=December 2007 The actual carrier fleet displacement in 1936 was closer to 165,000 tons, the displacement of only two "Forrestal"-class supercarriers of just twenty years later.

The naval treaty had a profound effect on the Japanese, many of whom saw the 5:5:3 ratio of ships as another way of being snubbed by the West (in fact, the Japanese, having a one-ocean navy, had a far greater concentration of force than the two-ocean United States Navy or the three-ocean Royal Navy). It also contributed to a schism in high ranks of the Imperial Japanese Navy; on one hand were the Treaty Faction officers, and on the other were their opponents who were also allied to the ultranationalists in the Japanese army and other parts of the Japanese government. For Treaty Faction opponents, the Treaty was one of the factors which contributed to the deterioration of the relationship between the United States and the Japanese Empire. The unfairness, at least in the eyes of the Japanese, is also what led to Japan's renunciation of the Naval Limitation Treaties in 1936. Isoroku Yamamoto, who later masterminded the Pearl Harbor attack, held that Japan should remain in the treaty and was therefore regarded by many as a member of the Treaty Faction. His view was more complex, however, in that he felt the United States could out-produce Japan by a greater factor than the 5:3 ratio because of the huge US production advantage, on which he was expert, having served in the Japanese Embassy in Washington. He felt that other methods would be needed to even the odds, which may have contributed to his advocacy of the plan to attack Pearl Harbor. However, he didn't have sufficient influence at Navy headquarters nor in the government, and Japan left the treaty in 1936.

See also

*Washington Naval Conference


External links

* [http://www.ibiblio.org/pha/pre-war/1922/nav_lim.html Conference on the Limitation of Armament] Full text of the Washington Naval Treaty.

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Washington Naval Conference — The Washington Naval Conference was a military conference called by the administration of President Warren G. Harding and held in Washington, D.C. from 12 November 1921 to 6 February 1922. Conducted outside the auspices of the League of Nations,… …   Wikipedia

  • London Naval Treaty — The London Naval Treaty was an agreement between the United Kingdom, the Empire of Japan, France, Italy and the United States, signed on April 22, 1930, which regulated submarine warfare and limited naval shipbuilding.Terms of the TreatyIt was an …   Wikipedia

  • Second London Naval Treaty — The Second London Naval Disarmament Conference opened in London, the United Kingdom, on December 9, 1935. It resulted in the Second London Naval Treaty which was signed on March 25, 1936. The signatories were the governments of France, the United …   Wikipedia

  • Treaty Faction — The nihongo|Treaty Faction|条約派|Jōyaku ha was an unofficial and informal political faction within the Imperial Japanese Navy in the 1920s 1930s of officers supporting the Washington Naval Treaty.BackgroundThe Washington Naval Treaty , also known… …   Wikipedia

  • Treaty battleship — A treaty battleship was a battleship built in the 1920s or 1930s under the terms of one of a number of international treaties governing naval construction. [Sumrall, p.25 8] Many of these ships played an active role in the Second World War, but… …   Wikipedia

  • Naval tactics in the Age of Steam — The development of the steam ironclad firing explosive shells in the mid 19th century rendered sailing tactics obsolete. New tactics were developed for the big gun Dreadnought battleships. The mine, torpedo, submarine and aircraft posed new… …   Wikipedia

  • Washington Treaty — The Treaty of Washington may refer to: * Treaty of Washington (1805), between the Federal government and the Creek National Council * Treaty of Washington (1826), between the Federal government and the Creek National Council led by Opothleyahola …   Wikipedia

  • Treaty of Mutual Cooperation and Security between the United States and Japan — Japan US Treaty of Mutual Security and Cooperation, 19 January 1960. United States Japan Security Treaty Type Military Alliance Signed 19 January …   Wikipedia

  • Naval warfare — Sea power redirects here. For the magazine, see Seapower. The French (left) and British (right) lines at the Battle of Chesapeake Warfare …   Wikipedia

  • Naval history of Japan — History of Japan Paleolithic 35,000–14,000 BC Jōmon period 14,000–300 BC Yayoi period 300 BC–250 AD Kofun period 250– …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.