Highlight the reasons for the rapid economic development of the United States after the Civil War.

The main reason is the abolition of slavery, as a result there was a large flow of emigration, which provided unskilled labor. The process of capital accumulation went very quickly. The United States adopted the experience of other countries, used the latest technologies in science and technology. New institutes were built, which gave highly qualified specialists. The country was rich in useful resources: oil, copper, coal, iron.
The army was not large, so it did not require public investment. The domestic market expanded, and the demand for manufactured goods increased.