What was the main reason that the Anti-Imperialist League opposed the war between US troops and Philippine rebels?

The Anti-Imperialist League opposed the war because it viewed US control over the Philippines as a violation of the principles of democracy and self-government. Fighting Filipino rebels who wanted independence seemed immoral and inconsistent with the values the United States claimed to support. Therefore, the best answer is that the league believed the war was immoral and undemocratic.

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