Westward expansion impacted American society in many ways. Here are three:
- It made American society richer. Getting access to more land and more resources helped to make the country richer.
- It helped to promote the idea that the US had a "manifest destiny" to be a great power. Expansion was based on taking land from people (Indians and Mexicans) who were deemed inferior. This helped promote the idea that Americans were better than others and deserved more power.
- It is said to have helped create a more democratic and individualistic culture. By going out west, people became more self-reliant because they had to face hardships on their own.
The best answer ever written to examine this question is a paper by Fredrick Jackson Turner, "The Significance of the Frontier in American History," delivered to a gathering of historians in Chicago in 1893.
Three years prior to his writing this paper, the US Census department claimed that there nolonger existed on the North American continent a "frontier." There were no more savage lands left to be conquered and civilized.
The thesis of Turner's paper was that by constantly pushing the boundaries of the frontier, the "American spirit" was renewed. It forced individual Americans to rely on their own wits and strength, to solve problems, and to continually renew American culture. It was out of this sense of renewal of the indiviual, unleashed from the exercise of centralized power, that the idea of "rugged individualism" was born.
This spirit of renewal is captured on the Statue of Liberty, which welcomes the immigrant with these words:
"Give me your tired, your poor, Your huddled masses yearning to breathe free, The wretched refuse of your teeming shore. Send these, the homeless, tempest-tost to me, I lift my lamp beside the golden door!"
This spirit of renewal was captured by President Kennedy when he declared in May, 1961 that America would put a man on the moon by the end of the decade.
And, this spirit of renewal was captured by a Science Fiction TV show in 1966 which declared at the beginning of each episode:
Space: The final frontier
These are the voyages of the Starship, Enterprise
Its 5 year mission
To explore strange new worlds
To seek out new life and new civilizations
To boldly go where no man has gone before
In order to renew the American Spirit, we need a frontier. Fredrick Jackson Turner's point was that the American Way of Life was built upon a history of testing the boundaries of our existence. Other empires look at their monuments, their ruins, their ancient documents and say "This is who we once were."
America looks to the future. We conquer frontiers. We look for challenges. That's who we are. And when we cease to look for the next frontier. When we stop trying looking for the next challenge, that's when we will cease being Americans.