I will expand on the previous educator's points.
Indeed, westward expansion increased the nation's wealth. Shortly after the Civil War, in 1865, only about 40 miles of track had been laid for the Union Pacific Railroad. The line was completed in 1869. The Union Pacific made it possible to travel from New York to San Francisco in ten days—a time frame that shortened with the development of higher-speed trains. The ability to go from one part of the country to another made it possible to transport goods and people more efficiently. The train eliminated the previous dangers that existed for those who traveled West on wagon trains, including attacks by Native tribes and harsh weather conditions.
Westward expansion became a greater possibility, not only because of the belief in Manifest Destiny (that it was the fate of the United States to stretch its borders from one ocean to another) but also due to the Monroe Doctrine. President James Monroe introduced a policy in 1823, in the midst of a...
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