Imperial Japanese Navy demonstrated the same thing at Pearl Harbor (December 7, 1941) and in sinking HMS Repulse and HMS Prince of Wales The first chance to test the doctrine in a fleet action came at the Battle of theCoral Sea (May 3–8, 1942), but that encounter was indecisive Next came the Battle of Midway (June 4–5, 1942), where the IJN suffered a catastrophic loss of fleet carriers and naval air power from which it never fully recovered The Guadalcanal campaign (1942–1943) provided more opportunities for small fleet actions in the battles of Cape Esperance (October 11–12, 1942); the Eastern Solomons (August 23–25, 1942); Santa Cruz (October 26–27, 1942); and the naval Battle of Guadalcanal (November 12–15, 1942) As Samuel Elliot Morrison noted in his monumental history of the naval war, the old tactics of line of battle were rendered obsolete by advances in antiship aircraft, which demanded evasive action and rendered it “impossible to maintain the line under air attack.” Yet, the old battleship wing of the IJN still clung to line of battle dogma and the “decisive battle” delusion as late as the great fight at Leyte Gulf in 1944 Just as tellingly, the IJN deployed its submarines not to intercept enemy troop and resupply columns but to attack and reduce the number of the enemy’s capital ships in preparation for the always elusive “decisive battle” it sought between surface fleets Japanese submarines of all types, including midget submarines, were deployed to harry the ships of the U.S Pacific Fleet rather than to destroy merchantmen and force the USN to redeploy destroyers and shipyard capacity to building escorts Even this ill-advised submarine strategy had to be abandoned from 1943, as IJN submarines were converted into supply ships for stranded garrisons along the coast of New Guinea and across the South Pacific That need also affected construction, so that late-war Japanese submarine designs shifted away from lethality to increased cargo capacity To partly compensate for lost naval combat power, a base for 11 German attack U-boats and a supply boat was established at Penang in mid-1943 More U-boats arrived later, as Indian Ocean hunting was safer and more profitable for U-boats by that point than plying dangerous Atlantic waters Effective Axis submarine cooperation did not survive past the destruction of the last Kriegsmarine Milchkühe (“Milk Cows”) supply boats in Asia in the spring of 1944 The last four German and two converted Italian submarines in Asia were seized by the IJN when Germany surrendered in May 1945 Efforts to persuade Dönitz to send more boats to the Pacific failed, as he instead instituted REGENBOGEN, scuttling the U-boat fleet At its maximum, the IJN deployed a fleet of 200 submarines Poor doctrine and the shift from an attack to a supply role meant that Japanese submarines sank only 171 enemy ships to the end of the war A handful were important warships and a few were military auxiliaries, but nowhere near enough warships were sunk or damaged to turn the fortunes of the naval war The cost to Japan of that effort was to leave hardly dented the enemy merchant marine The IJN lost 128 lost boats and crews in a submarine effort that barely registered against the enemy order of battle The United States captured two I-400 “Toku”-class boats a week after the surrender At 400 feet in length, they were larger than any submarine built before nuclear vessels in the 1960s When the Soviet Union asked to inspect them, the USN took the boats to sea and sank them 561