The Philippine–American War (also referred to as the Filipino-American War, the Philippine War, the Philippine Insurrection, the Tagalog Insurgency) was an armed conflict between the First Philippine Republic and the United States that lasted from February 4, 1899 to July 2, 1902. The war was a continuation of the Filipino struggle for independence that began in 1896 with the Philippine Revolution. The conflict arose when the First Philippine Republic objected to the terms of the Treaty of Paris under which the United States took possession of the Philippines from Spain, ending the Spanish–American War.
On February 11, 1899—only one week after the first shots of the war were fired—American naval forces destroyed the city of Iloilo with bombardment by the USS Petrel and the USS Baltimore. The city was then captured by ground forces led by Brigadier General Marcus Miller, with no loss of American lives.
Months later, after finally securing Manila from the Filipino forces, American forces moved northwards, engaging in combat at the brigade and battalion level in pursuit of the fleeing insurgent forces and their commanders. In response to the use of guerilla warfare tactics by Filipino forces beginning in September 1899, American military strategy shifted to a suppression footing. Tactics became focused on the control of key areas with internment and segregation of the civilian population in "zones of protection" from the guerrilla population (foreshadowing the Strategic Hamlet Program that would be utilized decades later, during the Vietnam War). Due to unsanitary conditions, many of the interned civilians died from dysentery.
Major General Elwell Stephen Otis gained notoriety for some of his actions in the Philippines. Although multiple orders were given to Otis from Washington to avoid military conflict, he did very little to prevent the breakout of war. Otis refused to accept anything but unconditional surrender from the Philippine Army. He often made major military decisions without first consulting leadership in Washington. He acted aggressively in dealing with the Filipinos under the assumption that their resistance would collapse quickly. Even after this assumption proved false, he continued to insist that the insurgency had been defeated, and that the remaining casualties were caused by "isolated bands of outlaws".
Otis also played a large role in suppressing information about American military tactics from the media. When letters describing American atrocities reached the American media, the War Department became involved and demanded that Otis investigate their authenticity. Each press clipping was forwarded to the original writer's commanding officer, who would then convince or force the soldier to write a retraction of the original statements.
Meanwhile, Otis claimed that Filipino insurgents tortured American prisoners in "fiendish fashion". During the closing months of 1899, Aguinaldo attempted to counter Otis' account by suggesting that neutral parties—foreign journalists or representatives of the International Committee of the Red Cross—inspect his military operations. Otis refused, but Aguinaldo managed to smuggle four reporters—two English, one Canadian, and one Japanese—into the Philippines. The correspondents returned to Manila to report that American captives were "treated more like guests than prisoners", were "fed the best that the country affords, and everything is done to gain their favor." The story went on to say that American prisoners were offered commissions in the Filipino army and that three had accepted. The four reporters were expelled from the Philippines as soon as their stories were printed.
U.S. Navy Lieutenant J.C. Gilmore, whose release was forced by American cavalry pursuing Aguinaldo into the mountains, insisted that he had received "considerable treatment" and that he was no more starved than were his captors. Otis responded to publication of two articles concerning this by ordering the "capture" of the two authors, and that they be "investigated", therefore questioning their loyalty.
When F.A. Blake of the International Committee of the Red Cross arrived at Aguinaldo's request, Otis kept him confined to Manila, where Otis' staff explained all of the violations of international humanitarian law perpetrated by Filipino soldiers. Blake managed to slip away from an escort and venture into the field. Blake never made it past American lines, but even within American lines he saw burned out villages and "horribly mutilated bodies, with stomachs slit open and occasionally decapitated." Blake waited to return to San Francisco, where he told one reporter that "American soldiers are determined to kill every Filipino in sight."
McKinley's election victory in 1900 was demoralizing for the insurgents, and convinced many Filipinos that the United States would not depart precipitously. This, coupled with a series of devastating losses on the battlefield against American forces equipped with superior technology and training, convinced Aguinaldo 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.
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. In fact, during just 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 even seemed as if the Filipinos would fight the Americans to a stalemate and force them to withdraw. This was even considered by President McKinley at the beginning of the phase.
Following Aguinaldo's capture by the Americans on March 23, 1901, Miguel Malvar assumed command of the Philippine revolutionary forces. Batangas and Laguna provinces were the main focus of Malvar's forces at this point in the war, and they continued to employ guerrilla warfare tactics.
In late 1901, Brigadier General J. Franklin Bell took command of American operations in Batangas and Laguna provinces. In response to Malvar's guerrilla warfare tactics, Bell employed counterinsurgency tactics (described by some as a scorched earth campaign) that took a heavy toll on both guerrilla fighters and civilians alike. "Zones of protection" were established, and civilians were given identification papers and forced into concentration camps (called reconcentrados) which were surrounded by free-fire zones. General Bell insisted that he had built these camps to "protect friendly natives from the insurgents, assure them an adequate food supply" while teaching them "proper sanitary standards." The commandant of one of the camps referred to them as the "suburbs of Hell."