after the war of 1812 the federalist party faded away, leaving an "era of good feelings" in which only one party was important, under presidents james madison and james monroe. under monroe, the united states' policy in north america was the monroe doctrine, which suggested that europe should stop trying to control the united states and other independent countries in the americas. around this time, congress called for something called the "american system". the american system meant spending money on banking, transportation and communication. due to the american system, bigger cities and more factories were built. one of the big transportation projects of this time was the erie canal, a canal in the state of new york. by the 1840s, railroads were built as well as canals. by 1860, thousands of miles of railroads and telegraph lines had been built in the united states, mostly in the northeast and midwest.