What is a good American history topic that happened from 1870-1930?

Activism and Reform: The Progressive Era in America

Connecting the Country: The Effect of Railroads on Economic Progress and Prosperity in America

America and the Construction of the Panama Canal

Isolation vs. Involvement: American and the First World War

The Pros and Cons of Prohibition

Yellow Journalism and the Spanish-American War

Great Railway Strike of 1877

The China Relief Expedition of 1900 - the first time a President committed US forces to active combat operations overseas without seeking the approval of Congress,on the grounds that,as Commander-in-Chief of the armed forces,the President could send troops wherever he wanted whenever he wanted on his own authority.

There was the Great Depression and the Great Dustbowl. There were political scandals like the Teapot Dome scandal. There was the rise of unions, spurred by disasters like the Triangle fire.