Answer:
Social Darwinism would affect American Political thought because it is an ideology that justifies racism, discrimination, and promotes eugenesia, based on the application of the ideas of Darwin to a social context.
That is to say, Social Darwinism is the belief that some people or some groups of people are inherently superior to others, and as such, they deserve to be on top of society, and to override the desires or priorities of people or groups of people deemed to be inferior.
