Yes it was illegal. It was considered a violation of the amendments and that's why war was necessary to make people agree on something for once. The Confederate States made their own amendments once they seceded but technically, they never actually left the north so those new amendments were considered null and void.
Paris resulting in the treaty of Paris
I will campaign against my candidates to bring constitution to the economy and delegate.
Iron and steel--by the late 19th century the US became the world leader in iron ore and steel exports.
Access to natural resources and a lot of labor, the US was able to access iron ore which was a hot commodity and necessary for creating steel. If countries had the ability to create steel then they would just buy the iron ore. If they could not produce steel, then US Steel was the export for them. Steel industries dominated states like Pennsylvania, Ohio, Michigan, and Indiana.
