When the Roeblings and others arrived, the United States was in the later stages of an economic boom, but this ended in the financial Panic of 1837, reducing everyone's opportunities. Farmers were deeply affected by it as they often depended on credit to produce the next season's crops. But by the 1840s, the economy was improving and many Americans believed in the nation's manifest destiny to extend its borders and achieve greatness on the North American continent. Transportation between eastern industrial hubs and frontier farming markets had become a matter of both national and popular interest.