Casualties, Wartime labor, invasion, economic depression.
Answer: trenches. WW1 is famous for its trench warfare- a dangerous form of warfare that resulted in a lot of deaths as stalemates lasted for months.
The steamboat not only moved people, but also goods. With the high demand in goods and fuel for these boats; along came thousands of jobs in the coal mines and in the factories. The steamboat also led to thousands of new settlement across America's rivers, including the huge boom of Indiana's Ohio River Cities.
