Steel was important to industrial growth after the civil war because it was used to make steel rails for railroads. <span>n the years between the </span>American Civil War<span> and the end of the nineteenth century the modern U.S. industrial economy developed on the backbone of a good transportation infrastructure mainly railroads that were developed from steel.</span><span>
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Technological advances increased profit and productivity
They visited Mecca to worship their gods.
It meant that as soon as one country falls under communist control, another country would fall and so on. Vietnam at the time was split into North (communist) and South (being attacked by North) and the US didn't want communism to spread, reasoning that it might eventually come to the US if nothing was done.