In the early twentieth century, debates over U.S. imperialism intensified, with different perspectives on the role American power should play on the global stage. Utilizing the provided documents, analyze the varying viewpoints on American imperialism and explain how the documents reflect the historical context of the time. In your response, be sure to address the nature of U.S. expansionism and its implications for both domestic and foreign policy.

Document 1: A speech by President William McKinley advocating for imperial expansion in the Philippines.

Document 2: An excerpt from the writings of Mark Twain criticizing American imperialism.

Document 3: A political cartoon of the era illustrating public opinions on U.S. conduct abroad.