QUOTE(ichi_24 @ Nov 3 2013, 11:59 PM)
waaaaaaaaaaaaaaaaaaait aren't japs are forbidden from making subs according to previous treaty?
Naval Disarmament Treaties.The London Treaty of 1930. In 1930, a third conference in London brought together Britain, the United States, and Japan. This treaty established further limits on lighter classes of ships, including cruisers, destroyers, and submarines.Destroyer tonnage was limited to 1500 standard tons per unit, except that 16% of the destroyer units of each could be flotilla leaders of up to 1850 standard tons. All were limited to 5" (127mm) guns. Britain and the United States could build to 150,000 total tons and Japan to 105,000 total tons, a ratio of 7:10. This was an increase from the 6:10 ratio for battleships from the Washington treaty but did not satisfy the Imperial Navy's Fleet Faction.
Submarines were limited to 2000 tons surface displacement and guns of not more than 5.25" (130mm), though torpedo size and numbers was oddly left unrestricted. The number of coastal submarines (defined as those displacing less than 600 tons) was unlimited, but oceangoing submarines (those from 600 to 2000 tons displacement) were limited to a total of 52,700 tons per power. The submarine limitation was particularly resented in Japan (quoted by Carpenter and Polmar 1986):
The Naval General Staff in Tokyo was enraged at this. Equality of submarine tonnage was totally unsatisfactory. Japan's war games had show that she needed an absolute minimum of 78,000 tons. A strength of 52,700 tons would leave her short by two squadrons of submarines — sixteen boats — of what her planners considered necessary to the strategy of attrition. The results of the London Conference were thus looked upon as having placed Japan's national defense in jeopardy.Continuing resentment at the naval disarmament treaty structure led Japan to denounce the treaties in December 1934.The London Treaty of 1936. A further conference in London in 1935-1936 was desultory, since Japan had already announced its withdrawal from the limitations system. The participating powers (U.S., Britain, and France) agreed to continue limiting displacement to 35,000 tons and to reduce maximum gun caliber to 14" (356mm). However, the treaty stipulated that the maximum gun caliber would revert to 16" if Japan did not ratify the treaty within a year, and maximum displacement would increase to 45,000 tons if any navy built a ship exceeding the 35,000 ton limit. Japan failed to ratify the treaty, and the major powers promptly began building up their navies. However, the first U.S. and Japanese battleships built during this new arms race did not commission until late 1941. The British were a little faster off the mark, commissioning their first new battleships in 1940, but at the cost of building these battleships with 14" rather than 16" guns.
The legacy of the naval disarmament treaties is difficult to interpret. The signatory powers abode by the terms of the treaties in reasonably good faith until the collapse of the treaty system in 1935, largely because this was in everyone's interest. The treaties prevented "a naval race no one really wanted" (Friedman 1985) between Britain and the United States at a time when the foreign interests of these two nations were becoming increasingly aligned. Although the United States clearly had the means to win a naval arms race, the cost would have been ruinous. On the other hand, resentment of the terms of the disarmament treaties was widespread in Japan and contributed to the rise of ultranationalism, and the restrictions on American fortifications in the Pacific left the Philippines and Guam dangerously vulnerable. On balance, the treaties benefit Japan, leaving her with naval supremacy in the Far East and making any execution of Plan ORANGE far more chancy.
The treaties proved a particular point of contention within the Japanese Navy. The principal Japanese naval representative at the conference, Kato Tomosaburo, believed that the Japanese Navy was a deterrent against any American aggression, not a force preparing for inevitable war, and believed that it was folly for Japan to try to match the United States in an arms race. However, Kato Kanji, who was appointed as naval aide to the elder Kato at the conference, was a militantly nationalist proponent of building the largest fleet possible.
Curiously, public opinion in the United States tended to view the naval disarmament treaties as evidence that tensions had already been reduced in the Pacific, rather than as a means to reducing tensions. As a result, the United States did not even build up its light forces to the treaty limits. The Japanese saw things rather differently, and began an intensive program of construction of light forces.
The cruiser displacement limit of 10,000 tons proved a particularly onerous limitation on ship design, and while no treaty power designed ships from the outset that violated the limit, most ended up with overweight ships. This was particularly true of the Japanese, who were thousands of tons over weight when the other powers were hundreds of tons over weight, and it became more true as Japan prepared to withdraw from the disarmament treaties. Evans and Peattie (1997) believe that the Japanese designers lacked the experience to achieve precisely the design displacement, but they also believe that the Navy General Staff made demands for additional weapons systems that they knew would push the designs over the limit.