What reinforcement could have helped the Philippines in 1941?

What could the United States have deployed to the Philippines in 1941 without sharply escalating tensions?

Better senior command and a fully supported infantry division would help more than the available ships, whose air defense and torpedoes were serious limitations.

The counterfactual shifts from extra ships to the preparation of the land defense. A separate four-star commander for American forces and an infantry division with artillery and support are proposed as ways to build stronger defensive perimeters and improve preparation of Filipino troops. Surface ships available in June 1941 offered little protection against the aircraft that would attack those defenses before the landings. Additional submarines would also face the torpedo defects affecting the boats already present. Their limited use of deck guns then raises a separate uncertainty: fear of Japanese escorts is offered as an explanation, but the extent of that constraint remains disputed in the exchange.