Evaluate the relative importance of different causes for the expanding role of the united states in the world in the period from 1865 to 1910

The period between 1865 and 1918, including 1910, was extremely important for the building of the United States as a nation and its establishment as a world power with a really vital role to play in the region and worldwide.

After the end of the Civil War, and starting from the Reconstruction, until high into the 20th century, the United States saw the arrival of really prosperous times in the economic, agricultural and industrialization fronts that led the country not only to grow, but also to become the center of attention for European immigration and for an expansion in the American role in international arenas. It is then, at this time, that the United States lives through three very important periods: Reconstruction Era, the Gilded Age and the Progressive Era.

Because of the end of slavery,  due to the influx of laboring hands from African Americans, and the changes made by the end of the war, the North and West saw a big increase in production and prosperity thanks to the growth of agricultural power and production. Another area that was benefitted was industrialization, as with the appearance of wealth and prosperity, many new minds set themselves to developing new technologies, such as steel, and the telegraph, that bolstered the increase of new industrial production. Communications and especially transport, also helped here, especially with the building of new and improved railroads and train systems. Another important factor was the abundance of natural resources in the land, including minerals and others, which bolstered production and development and gave a boost to what is known as the Second Industrial Revolution. Migration also became really important as it led to urbanization and an expansion of laboring hands to all territories of the country, further improving production.

In the end, all these factors, and others, contributed to the United States building as a really strong nation, and now politically stabilized, the country focused outwards to the overseas. In fact, America had, at some point, a small empire, with the acquisition of Alaska in 1867, Puerto Rico and some other smaller islands, as well as the annexation of Hawaii in 1898. Later on, they would further expand after defeating Spain in the Spanish-American war in 1898 and earning the independence of Cuba and in 1946, it also brought in the control of the Philippiness for a period of time.

they united the colonies in their fight against the british.

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