They created more jobs to better the economy. These jobs mostly in manufacturing as that would be best for the war effort.
In the early 19th century, settlers could travel from 15 to 20 miles per day by covered wagon. Given the distance between New York and California is around 2,445 miles, the journey would take approximately 122 to 162 days, or from 4 to 5.5 months.
Have a great day!~ <3
