Answer: The level of government in which I think should be in charge of security is going to have to be federal. Because the federal government deals with the nation’s affairs and laws. Security from foreign enemies is a national concern meaning that the federal government should take care of the nation’s defense. Which they do of course. The Department of Defense is an executive branch department of the federal government of the United States charged with coordinating and supervising all agencies and functions of the government concerned directly with national security and the United States Armed Forces.
It increased the demand for steel since steel was used to make railcars and tracks.
Steel was used to make railroad tracks and cars because it was the only metal strong enough. So the expansion of the railroad industry would mean more steel had to be used and thus it would increase the demand.