The extent to which the old GOP was progressive is greatly exaggerated. Republicans were already the conservative party by the time that Roosevelt came along. Teddy himself was never meant to be the president, it's just that the conservative president William McKinley died.
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But to answer your question. Yes, they did adhere to classical liberalism. American politics before 1900 was just different factions of liberalism competing against each other.
Styrofoam_Snake t1_j8wqoev wrote
Reply to Did both parties adhere to classical liberalism in the early 1900s? What were the ideological differences between the parties in general and with respect to Progressivism? by Convenience21
The extent to which the old GOP was progressive is greatly exaggerated. Republicans were already the conservative party by the time that Roosevelt came along. Teddy himself was never meant to be the president, it's just that the conservative president William McKinley died.
​
But to answer your question. Yes, they did adhere to classical liberalism. American politics before 1900 was just different factions of liberalism competing against each other.