Final answer:
Support for the annexation of the Philippines was driven by the desire to access Asian markets, the strategic value of the islands as a safeguard against other imperial powers, and an imperialist ideology that posited the U.S. had a duty to civilize and educate the Filipinos.
Step-by-step explanation:
There were several reasons why some people in the United States supported the annexation of the Philippines.
First, the economic interest in accessing Asian markets, particularly trading with China, was a significant motivator. An American presence in the Philippines was seen as a gateway to lucrative trade opportunities in Asia.
Secondly, the strategic value of the Philippines appealed to those who were concerned about national security. There was a prevailing fear that if the United States did not take control, other imperial powers such as Germany, Japan, or Britain would, posing a threat to American interests in the Pacific.
Third, a sense of imperialist duty and the belief in the civilizing mission were at play, echoing the sentiments of figures like Theodore Roosevelt and Senator Henry Cabot Lodge, who felt that the U.S. had a role in liberating and educating the Filipino people, in line with the ideology of 'The White Man's Burden'.