Why has the battle of Gettysburg been called "the most crucial battle in American history"

The two sides met and fought near the town of Gettysburg, Pennsylvania. The battle at Gettysburg has been called "the most crucial battle in American history."

This was because, before the Battle of Gettysburg, the Confederacy had been doing very well in the Civil War. But at Gettysburg, the North defeated the South. The Union Army suffered 23,000 casualties, while the Confederate Army suffered 28,000.

Explanation: