If Japan concentrated on the Philippines instead of Pearl Harbor

How would the Pacific War change if Japan destroyed the main U.S. fleet in the Philippines instead of striking Pearl Harbor?

The war could last roughly eighteen months to two years longer because the United States would need time to replace the lost fleet.

Japan historically attacked the Philippines as well as Pearl Harbor and rapidly defeated much of the force there. The stronger counterfactual requires the United States to base its main fleet in the Philippines and Japan to destroy that fleet with the concentrated Kido Butai. Such a loss would remove far more than an advance base because it would consume the trained crews and ships needed for the early counteroffensive. Rebuilding could extend the war by about eighteen months to two years.