When discussing the Pacific War, some naval clashes loom larger than others. The Battle of the Philippine Sea (19-20 June, 1944) is often overlooked in favour of the Coral Sea, Midway, or Leyte Gulf. Yet the Battle of the Philippine Sea was a decisive moment in the struggle for the Pacific.
1. The battle occurred during the US invasion of the Mariana Islands
The Japanese sought a decisive clash with the US fleet while US forces were fighting on the island of Saipan. The Marianas were a key strategic position for the Japanese. Not only did they have aircraft based there but losing the islands would open the way for the US to reach the Philippines and even the Japanese mainland.
2. US aircraft and pilots outmatched the Japanese
At Midway in 1942, the Japanese possessed better aircraft and impeccably trained pilots. By 1944 the tables had turned. The US had replaced the Wildcat with the Hellcat as their primary carrier fighter, capable of outmatching the Zero. Meanwhile, losses had stripped the Japanese navy of its best pilots.
3. The US had perfected their carrier doctrine
Alongside the qualitative improvements in aircraft, the US Navy introduced the Combat Information Centre – the equivalent of today’s Operations Room – where radar and communications information was centralised. Better aircraft, better intelligence, better coordination, and more powerful antiaircraft defence came together at the Philippine Sea to ensure that, of 450 Japanese aircraft committed to battle, over 90% were destroyed.
4. The battle rendered Japanese fleet carriers impotent
With 90% of the carrier aircraft committed to the battle destroyed, the IJN was left with insufficient airpower to man its remaining fleet carriers, which would play only a minor role for the rest of the war.
5. The victory might have been even more overwhelming
In the aftermath of the battle, and in the decades since, historians have debated the decision by Admiral Raymond Spruance not to pursue the remnants of the Japanese fleet. Spruance instead chose caution, and to protect the US beachhead on Saipan. Had Spruance ordered the pursuit then the Japanese defeat could have been even more complete, and future encounters, including the Battle of Leyte Gulf, may never have happened.
The Battle of the Philippine Sea left the Japanese carrier force impotent and secured the US beachhead on Saipan. The subsequent loss of Saipan, Guam, and the other Mariana Islands came as a crushing blow to the Japanese and left the US poised to move on the Philippines.