The answer is 'Railroads'
The Industrial Revolution in England lead to the development of trains and fast travel.
The United States quickly adopted the technology and brought in English businessmen and engineers to develop railroads in it's sprawling western states.
Railroads were integral in the early years in to cement newly acquired states under the control of the Federal government.
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<span>The world war 2 brought the U.S. together socially, it made America a supper power, it brought the us out of a recession, and unfortunately led the U.S closer to socialism.
I hope my answer has come to your help. God bless and have a nice day ahead!
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