Answer: C. They were scared that the war would resume and didn't want to get their hopes up.
Explanation: I know this is late but may it help someone.
Answer:
How did the American economy change in the 19th century?
From the era of Reconstruction to the end of the 19th century, the United States underwent an economic transformation marked by the maturing of the industrial economy, the rapid expansion of big business, the development of large-scale agriculture, and the rise of national labor unions and industrial conflict.
It made production quicker
Probably nuclear because as seen in the bombing of Hiroshima & Nagasaki, both cities were leveled with ruins of building left.
