How did some american politicians justify u. s. imperialism at the end of the 19th century

One of the main ways in which some American politicians justified US imperialism at the end of the 19th century was by saying that the US was "helping" these distant lands by implementing a more sound social and economic system. 

Delaware, pennsylvania, new jersey, georgia, connecticut, massachusetts bay, maryland, south carolina, new hampshire, virginia, new york, north carolina, and rhode island and providence plantations where the 13 original colonies

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