Why the 6-6 fleet still needed light forces

The 6-6 plan aimed to make an attack on Japan costly enough to deter an invader. Six strong battleships formed its core, while six large armoured cruisers were expected to hold part of an enemy battle line until the battleships could win elsewhere. Japan paid for improvements to contemporary British battleship designs because it ordered only one or two ships at a time. Repeating the same extra cost across a British order of a dozen could substantially reduce the number affordable. Of each group of six, two ships would normally be fully operational and two more available to call upon, allowing four to be maintained for wartime operations close to Japan. Four battleships and four large armoured cruisers appeared at Tsushima. Destroyers brought a torpedo threat to this force that an invader also had to counter.