Answer:
Frederick Jackson Turner argued that overseas expansion was a "safety valve" to keep ambitious Americans content.
President James Monroe announces another U.S. outside strategy activity that winds up plainly known as the "Monroe Doctrine." The neutralist position of the Monroe Doctrine was likewise a foundation of U.S. remote approach in the nineteenth century, and it took the two world wars of the twentieth century to draw a reluctant America into its new part as a noteworthy worldwide power.
Spain and the United States i think
