Answer:
Manifest Destiny was the idea that Americans, that is to say, the United States, had the right to expand to the West, and reach the Pacific Ocean: occupy the lands in between, and spread American values.
It also applies to other parts of the world in a more indirect way, especially Latin America.
The settlement of the West was aided both by economic necessity, because many migrants were arriving in the United States seeking for cheap land, and also by ideology, and the ideology was precisely that of Manifest Destiny.
A nations power based on wealth is called is usually referred to as GDP, or "Gross Domestic Product" (if I'm understanding the question correctly. Although this isn't always a great indicator of the fundamental "health" of the country.<span />
Answer:
Are you sure 1965 is right?? Could it be 1865? I think you are looking for the Gilded Age from late 1860s to 1900.
Explanation: