Answer:
Children were paid less, and since they were smaller, they could do tasks adults coudn't do easily.
They were also less likely to rebel/strike against their working conditions (Thier working conditions were not good).
From Boston to New York city
This quote means that if you choose the job of your dream, you won't feel like your working, it feels like a fun dream your whole life.
This is optimistic because it is saying that if you do what you love you'll be happy.
It will make people want to choose the best job for them so that they can do what they want their whole life!
There are several reasons why militarism made it more difficult to avoid the outbreak of war, but mostly because nations had invested so much money into weapons they couldn't do anything else.