Answer: The expansion of railway lines throughout the West
Explanation:
To say that the Railroad only contributed minutely to the development of the United States as a nation would be a gross injustice. The establishment of railway lines to any part of the country brought prosperity and drove its development.
This was especially true for states in the west such as Washington, Idaho, Montana, Utah and Wyoming. With the expansion of railway lines throughout the west and into these territories, their populations increased and enabled the states to press for and get awarded with statehood.
