How did technology lend to geography expansion and growth of cities in the 1800s in the United States?

The rapid expansion of big business, the development of large-scale agriculture, and ... An outburst of technological innovation in the late 19th century fueled this ... making the United States the world's premier food producer--a position it has ... This led to wars against the Native Americans of the Plains.

to protect the united states' role as a world leader, president truman wanted to prevent the soviet union from spreading communism beyond its post-world war ii boundaries. he declared that the united states must assist any nations struggling to prevent a communist takeover.

slavery, abortion, donald trump, gay marriage, racial rights, immigration  

explanation:

anything that has been broth up to the supreme court is something of grate political divide   so just look as court cases