Many countries in Africa and Asia possess equal advantages, but they are not equally prosperous.
This leads me to the consideration of another reason for America's growth.

The men who have migrated to the United States have not been rich people.

They went there to make a living.

They were prepared to work, their purpose was to improve their condition, and they were willing to undertake any manual or mental labor to accomplish their object.

They were hardy and strong and could bear a heavy strain.
Their children inherited their good qualities, and so an American is generally more hard working and enterprising than most of the people in Europe and elsewhere.
Another reason for America's success is the great freedom which each citizen enjoys.