The capture of the Philippines by the Americans would ring the death knell for the Imperial Japanese Navy. The shipping lanes to Java and the Dutch East Indies, already under constant air and submarine attack, would be finally and definitively cut. All of Japan’s remaining naval strength would be committed to the coming battle. They had no choice: any ships remaining north of the Philippines would be without fuel, and because naval shells were only manufactured in Japan, any ships remaining south of the Philippines would be without ammunition.
Coordinating the far flung Japanese naval task forces necessitated a complex plan, named Sho Go I by the Imperial Japanese General Staff. (Operation Sho-Go I was a branch of Operation Sho-Go, the defense of the Home Islands.) Though complicated, if Sho-Go I was successful, the American 7th Fleet would be destroyed, the 3rd Fleet would be hamstrung, and MacArthur’s forces would be thrown back into the sea. America would suffer a huge strategic loss and (it was thought) be compelled to come to a negotiated cease fire. The importance of Sho-Go I was not lost on the Japanese Navy’s bitterest rival, the Japanese Army. In a rare moment of interservice cooperation, Sho-Go I was made even more complicated by including the Japanese Army on Leyte and Luzon. Tomoyuki Yamashita, the commander and governor of the Japanese occupied Philippines, reinforced Leyte with every aircraft he had left, and enough troops to drive the Americans back into the sea after they lost their supporting ships offshore.
The Americans were convinced that carriers were the key to naval warfare (they were) but in the narrow confines of the Philippine archipelago, the Japanese could use their remaining battleships to force this Kantai Kessen, or decisive battle to end the war. But the battleships had to get there first and America’s carriers were in the way. The key to Sho-Go I was Admiral Marc Mitscher’s powerful Task Force 38 which consisted of all of America’s big fleet carriers. It was this TF that smashed Japan’s remaining carrier airpower at the Battle of the Philippine Sea aka The Great Mariana’s Turkey Shoot. For the Japanese plan to have any success, TF 38 had to be neutralized.
Lacking any carrier air power at all, the Japanese chose to neutralize TF 38 through deception. The Japanese Northern Force consisted of their remaining four carriers, but almost no planes, and definitely no trained carrier pilots. But it would be a target the carrier-mad Americans could not resist. The Northern Force was the bait to lure TF 38 away from the Philippines. Once they were spotted, the Northern Force would race back north, away from the Philippines, with TF 38 in pursuit.
Once TF 38 was gone, the Southern Force, steaming north from Java would enter the Leyte Gulf via the Surigao Strait. At the same time, the powerful Center Force under Vice Admiral Takeo Kurita, consisting of eight battleships, including the super battleships Yamato and Musashi, was steaming east from Formosa, and it would enter the Leyte Gulf via the San Bernardino Strait off the island of Samar. Together they would smash MacArthur’s invasion fleet. Yamashita would then be free to destroy an outnumbered and cut off US Sixth Army on Leyte. On 22 October 1944, all three Japanese task forces were converging on Leyte. They were under radio silence, and the plan could not be altered.
TF 38 had to take the bait for Sho-Go I to work. The fate of the entire Imperial Japanese Navy depended on it. Luckily for the Japanese, sailing with TF 38 was the key to any success they would have in the upcoming operation: American Admiral Bull Halsey. Bull Halsey was America’s greatest carrier admiral, but he was proud, and his lack of any big Jap fleet carrier kills was a sore point in the wardroom. He always seemed to just miss them: He and his carriers were too far away to intervene at Pearl Harbor. Though Coral Sea was a victory, his carriers only sank one small escort carrier. Halsey missed Midway because he was in the hospital with a bad skin rash. The Japanese carriers were not an important target with all the important Japanese bases in the Solomon’s. And finally, he was away from TF 38 during the Great Mariana’s Turkey Shoot. The Northern Force was the last opportunity for Halsey to sink a Japanese carrier in the war. The Japanese were convinced Halsey would not pass it up and based their entire plan on it.
They were right.