Which strategy did Filipino insurgents employ against U.S. forces?

The strategy employed by Filipino insurgents against U.S. forces was guerrilla warfare. This tactic involved small, mobile groups of combatants using hit-and-run techniques, sabotage, and ambushes rather than engaging in direct, large-scale confrontations. The guerrilla warfare approach was particularly effective for the Filipino forces due to their familiarity with the terrain, which allowed them to evade larger and more equipped U.S. forces.

Filipino insurgents faced a technologically superior army; therefore, traditional fighting methods, such as open field battles, would have favored the U.S. military's advantages in equipment and manpower. Instead, by utilizing guerrilla tactics, they were able to exploit their knowledge of the environment and engage in asymmetric warfare, targeting vulnerabilities in the U.S. military's operations.

Furthermore, while naval blockades and trench warfare were tactics employed in other conflicts, they were not applicable or effective in the context of the Philippine-American War, where mobility and stealth were crucial for the insurgents' success. This illustrates how the choice of guerrilla warfare allowed Filipino fighters to adapt to their circumstances and continue resistance against a more powerful adversary.