Answer:
The World War 1 experience impacted hugely on U.S. culture, domestic politics and society. The war also resulted in an increased demand for weapons abroad. This led to increased profits and heightened productivity in the American steel industry. World War 1 ushered in an era of using chemical weapons.
I would have to go with Completion of the transcontinental railroad in 1869
Yes they do lie between both tigris and euphrates mountains
