Answer:
The westward expansion became the identity of America and served as cultural ties to European because it drove the people to express their identity in America. Majority of the people who came to settle in America were from a European background. People were experiencing and mixing among the Americans as well as following their European culture. Westward Expansion gave them the freedom to practice their customs in America and helped in giving America its identity. That's the reason we see different types of European countries people living in America.