There is no single reason why the United States underwent such a remarkable transformation in the period after
1870. Many related factors played a part. These ranged the availability of raw materials such as coal and iron ore, to the attitude of the government. There was no point in businessmen building factories to make clothes, for example, if there was no transport system to bring in the necessary raw materials and take away the finished products. There had to be a supply of energy to drive the looms to make the cotton and plenty of labour to work them. There had to be capital available to enable the factory owners to borrow the money needed for their new machines at a reasonable rate of interest. There also had to be a demand for the clothing and consumers needed to be able to afford to buy it
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