Regarding any suggested submarine blockade of Japan - by 1944 the Allied command of the Pacific was dominated by the US Navy who by then had so decimated Japanese shipping that even lowly rice carrying barges
were considered a worthy target. RN offers to assist the USN were
bluntly ignored or turned down by the US CinC of the Pacific Theatre of War (beleived Admiral King who was extremely anti-British) In addition
the Allies were faced with realising that the Japanese code of honour
meant they could be counted on to fight to the death - together with Kami Kaze attacks resulting in huge US casualties.
A tragic result of the American success in destroying and sinking vast numbers of Japanese shipping being that often their darkened holds contained hundreds of half starved skeletal Allied POWs on their way to work as slaves in Japanese coal mines or factories etc who would suffer
death blown to pieces or would drown in their battened down prison holds.
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