Second London Naval Treaty

From Wikipedia, the free encyclopedia

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 Kingdom, and the United States of America. The government of Japan, which had been a signatory of the First London Naval Treaty, had withdrawn from the conference on January 15. Italy also declined to sign the treaty, largely as a result of public hostility over her invasion of Abyssinia.

The conference was intended to limit the growth in naval armaments until its expiry in 1942. The absence of Japan (a very significant naval power) prevented agreement on a ceiling on the numbers of warships. The treaty did limit the maximum size of the signatories' ships, and the maximum calibre of the guns which they could carry. First of all, capital ships were restricted to 35,000 tons and 14-inch (356 mm) guns. An escalator clause was included which allowed capital ships 16-inch (406 mm) guns if any other party to the Washington Naval Treaty fail to agree to conform to this provision by 1 January 1937. Also submarines could not be larger than 2,000 tons or have a gun armament of greater than 5.1-inches, cruisers were restricted to 8,000 tons and 6.1-inch (155 mm) or smaller guns and aircraft carriers were restricted to 23,000 tons. Article 25 however gave the right to depart limitations if any other country authorised, constructed or acquired a capital ship, an aircraft carrier or a submarine exceeding treaty limits, if such a departure would be necessary for the national security. For this reason, in 1938 the treaty parties agreed on a new displacement limit of 45,000 tons.

This treaty effectively ended on 1 September 1939 with the beginning of World War II. Even during its brief period of supposed effectiveness, its clauses were honored more in the breach than in the observance; the only "treaty" cruisers the United States commissioned (the St. Louis class light cruisers, for example, were over 5,000 tons heavier than the treaty tonnage - in fact they were laid after signing a treaty, but before it came into force). Three classes of "Treaty" Battleships were built by the United States: the North Carolina class, the South Dakota class, and the Iowa class. The design of the North Carolina class was initiated before the escalator clause was invoked. The ships of the class were intended to be armed with, and protected against, 14-inch guns. However, with the invocation of the escalator clause, they were completed with 16-inch guns. The "SoDaks" were designed with and protected against 16-inch guns, but maintained a 35,000 ton standard displacement.

The Iowa class was designed after the beginning of World War II and took full advantage of the escalator clause (16-inch guns, 45,000 standard displacement); other than the monstrous Yamato class, the Iowa class was the heaviest class of battleship ever put to sea (Vanguard was heavier than the Iowas at standard loading, but lighter at full load).

Article 22 of the 1930 Treaty of London relating to submarine warfare declared that international law applied to them as to surface vessels. Also merchant vessels which did not demonstrate "persistent refusal to stop" or "active resistance" could not be sunk without the ship's crew and passengers being first delivered to a "place of safety". The 1936 treaty confirmed that Article 22 of the 1930 treaty remained in force, and "all others Powers [were invited] to express their assent to the rules embodied in this Article" ^[1] ^[2] It was this provision which was used at the post war Nuremberg Trial of Karl Dönitz for ordering unrestricted submarine warfare.