British Far East fleet plans and imperial scale

Were British war plans for Japan delusional compared with the American Pacific approach?

No. Britain planned around imperial bases and a large fleet renewal for 1942, a different logistical solution from American trans-Pacific operations.

British planning for Japan did not copy the American trans-Pacific approach because Britain expected to fight from imperial bases and resources already on the far side of the world. The United States faced the logistical burden of crossing the Pacific, while Britain also had to prepare for possible war in Europe. From 1932, the Royal Navy planned a major renewal that gained funding in 1937 and aimed at roughly twenty-five capital ships, about a dozen carriers, new cruisers, destroyers, supply ships, and oilers from 1942. Hunt-class escorts, Flower-class corvettes, and Black Swan-class sloops show that the supporting fleet was being designed and ordered before the war. The plan was ambitious, and its viability depended on the international conditions for which it had been built.