Why did the united states largely shy away from imperialism prior to 1890?

The main reason why the United States largely shied away from imperialism prior to 1890 was because it was still a relatively "fragile" nation with a host of its own issues to work out--such as the slavery issue that eventually led to the devastating Civil War. 

Your answer should be choice b!

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