On 21 July the chief of the naval general staff, Imperial General Headquarters, issued a directive for subsequent “urgent operations.”[11] The operational policy to be followed by the Combined Fleet was as follows:
1. Make utmost effort to maintain and make advantageous use of the strategic status quo; plan to smash the enemy’s strength; take the initiative in creating favorable tactical opportunities, or seize the opportunity as it presents itself to crush the enemy fleet and attacking forces.
2. Co-operate in close conjunction with the Army, maintain the security of sectors vital to national defense, and prepare for future eventualities.
3. Co-operate closely with related forces to maintain security of surface routes between Japan and vital southern sources of materials.[12]
On 26 July the chief of the naval general staff informed Admiral Toyoda, Commander in Chief, Combined Fleet, that the future “urgent operations” were to be known as the SHŌ (Victory) Operations. There would be four SHŌ Operations. The first was to cover the defense of the Philippine Archipelago.[13] It was essentially the last chance for Japan to remain in the war. Said Admiral Toyoda of the situation at the time of the battle of Leyte Gulf:
Since without the participation of our Combined Fleet there was no possibility of the land-based forces in the Philippines having any chance against your forces at all, it was decided to send the whole fleet, taking the gamble. If things went well, we might obtain unexpectedly good results; but if the worst should happen, there was a chance that we would lose the entire fleet. But I felt that that chance had to be taken.... Should we lose in the Philippines operations, even though the fleet should be left, the shipping lane to the south would be completely cut off, so that the fleet, if it should come back to Japanese waters, could not obtain its fuel supply. If it should remain in southern waters, it could not receive supplies of ammunition and arms. There would be no sense in saving the fleet at the expense of the Philippines.[14]
Since their carrier force was weak, the Japanese had developed a plan based upon the main gunnery strength of the fleet and upon the land-based air forces. Battleships and cruisers from a southern base were to approach Leyte from the south, fight their way to the landing beaches, and destroy Allied assault shipping. A decoy force was to attempt to lure the U.S. carrier task force away from the main action. Shore-based air forces were to inflict maximum damage on the American carrier forces whenever and wherever possible, but once the invasion came they were to conserve their strength until the day of the landings, when all the Allied assault shipping would be concentrated off the beaches and when their attacks on the U.S. carriers would assist the advancing Japanese fleet. The plan was designed to get the Japanese naval gunnery force into a position where it could do the greatest damage. Little attention was paid to getting it out. “The war had reached a point where the Japanese fleet, hopelessly outnumbered and, as imminent events would prove, even more hopelessly out-classed, could not risk the fleet action it had previously desired but was forced to expend itself in suicidal attack upon the United States transports.”[15]
Upon receiving information on 17 October that American vessels were off the shores of Suluan Island, Admiral Toyoda immediately alerted his forces. On 18 October Toyoda, after intercepting American messages dealing with the landings on the island approaches to Leyte Gulf, activated his plan for the defense of the Philippine Islands. The target date (X Day) for the fleet engagement was set for 22 October but logistical difficulties caused a series of delays and on 21 October Admiral Toyoda changed X Day to 25 October. “From the far corners of the shrinking Empire the whole combatant strength of the Japanese Navy converged on Leyte Gulf.”[16]
The Naval Battle[17]
The strongest Japanese naval force—the 1st Diversion Attack Force—moved from the south, reached Brunei Bay in northwest Borneo on 20 October, and after refueling split into two parts and proceeded on its way two days later. The main strength of the 1st Diversion Attack Force, under Admiral Kurita, sailed northeast up the west coast of Palawan (one of the Visayan Islands), and then turned eastward through the waters of the central Philippines to San Bernardino Strait, while the smaller unit commanded by Vice Adm. Shoji Nishimura moved eastward through the Sulu Sea in order to force an entrance at Surigao Strait. The 2d Diversion Attack Force, commanded by Vice Adm. Kiyohide Shima, after leaving the Pescadores on 21 October, sailed south, past western Luzon, and after refueling in the Calamian Islands, just south of Mindoro, proceeded to follow and support the southern part of the 1st Diversion Attack Force in forcing Surigao Strait.