Technological advances transformed America in the last quarter of the nineteenth century, the period known as the Gilded Age. Enterprising Americans built on the innovations of the first Industrial Revolution and the national networks of transportation and communication established by railroad track and telegraph line earlier in the century. They created new industries and tapped into a truly national market for manufactures and consumer goods. By 1900, the turn of the century and what historians refer to as the Second Industrial Revolution, American society was one of mass production, mass consumption, and mass marketing, and the nation was poised to assume the global lead in technology and industry. In short, the United States emerged from the final decades of the nineteenth century as an increasingly urban, heavily industrialized world power—the product of a technological transformation that profoundly altered American life and society in every respect.
If the Civil War violently demonstrated that the United States was one nation politically, the technology-driven events of the 1880s and 1890s would draw the nation together economically, socially, and culturally as never before.
The America we now know was molded in those years of change. The contours of the society we consider to be "modern" were established largely through the innovations of the last quarter of the nineteenth century. Someone born into middle- or upper-class society in the 1880s might very well have been a telephone-using, streetcar-riding, motion-picture-watching, Coca-Cola-drinking suburban teenager by the early 1900s. Starting to sound familiar?
And while it's hard to draw a line in history saying "modern America starts here," it's easy to see that by 1900 the historical "them" were starting to look a lot like present day "us."