<P> McKinley's election victory in 1900 was demoralizing for the insurgents, and convinced many Filipinos that the United States would not depart quickly . Coupled with a series of devastating losses on the battlefield against American forces equipped with superior technology and training, Aguinaldo became convinced that he needed to change his approach . Beginning on September 14, 1899, Aguinaldo accepted the advice of General Gregorio del Pilar and authorized the use of guerilla warfare tactics in subsequent military operations in Bulacan . </P> <P> For most of 1899, the revolutionary leadership had viewed guerrilla warfare strategically only as a tactical option of final recourse, not as a means of operation which better suited their disadvantaged situation . On November 13, 1899, Emilio Aguinaldo decreed that guerrilla war would henceforth be the strategy . This made American occupation of the Philippine archipelago all the more difficult over the next few years . During the first four months of the guerrilla war, the Americans had nearly 500 casualties . The Philippine Army began staging bloody ambushes and raids, such as the guerrilla victories at Paye, Catubig, Makahambus, Pulang Lupa, Balangiga and Mabitac . At first, it seemed that the Filipinos might be able to fight the Americans to a stalemate and force them to withdraw . President McKinley considered withdrawal when the guerrilla raids began . </P> <P> On December 20, 1900, General Arthur MacArthur Jr., who had succeeded Elwell Otis as U.S. Military Governor on May 5, placed the Philippines under martial law, invoking U.S. Army General Order 100 . He announced that guerilla abuses would no longer be tolerated and outlined the rights which would govern the U.S. Army's treatment of guerillas and civilians . In particular, guerrillas who wore no uniform but peasant dress and shifted from civilian to military status would be held accountable; secret committees that collected revolutionary taxes and those accepting U.S. protection in occupied towns while assisting guerillas would be treated as "war rebels or war traitors". Filipino leaders who continued to work towards Philippine independence were deported to Guam . </P> <P> The Philippine Army continued suffering defeats from the better armed United States Army during the conventional warfare phase, forcing Aguinaldo to continually change his base of operations . He did this for nearly the length of the entire war . </P>

The leader of u.s. forces in the philippines during the filipino war was
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