What is significant about the Gettysburg Address?

The Gettysburg Address, is a signficant piece, because it is what make's the U.S. what it is today. Before, President Lincoln's speech the U.S. was known as the United State's are. Which state's that each state is on its own, but after his speech it was known as the Untied States is which puts the U.S. as a whole.