The period from the 1880s through hte 1920s was a departure from traditional American foreign policy. To waht extent was hte foreign policy of the United States a departure from our traditional spirit of isolation during these decades?

I analyzed the documents well and I know why it deviated from isolationism. But what evidence is there that the U.S. was isolationist prior to the 1880s. If anyone knows anything that shows isolation in U.S. policy, please help me out!

Thanks so much,
becker21