Maybe higher security and enforced laws over time
Also more morals and equality, especially against blacks.
Also the aftermath of the world wars- what was learned from it
The Manifest Destiny which stated that the U.S. had a God-given right to all of the land in North America
Answer:
The available evidence suggests that immigration leads to more innovation, a better educated workforce, greater occupational specialization, better matching of skills with jobs, and higher overall economic productivity. Immigration also has a net positive effect on combined federal, state, and local budgets.
More factories opened and more people moved to urban areas