Question

How did the U.S. expand in the late nineteenth century?

Answer 1

The late 19th-century United States is probably best known for the vast expansion of its industrial plant and output. At the heart of these huge increases was the mass production of goods by machines. This process was first introduced and perfected by British textile manufacturers.

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Answer 2

They were in expanding to the west by buying land to kicking its former occupants to the curb (mexican american war) the us would do anything to get new land.