In 1801 Eli Whitney invented another key part to the industrial revolution, interchangeable parts.  Eli made the first musket out of interchangeable parts.  With interchangeable parts you could replace the individual part instead of the whole thing if something broke.  Interchangeable parts were cheaper to make than to make a whole item.  Also interchangeable parts could be manufactured faster and required less skilled workers than before.  Now, America had all the parts it needed for an industrial revolution, it just needed something to set the whole thing in motion.  The War Of 1812 was just the thing we needed.  At the time America got most of their goods from Britain.  So when we went to war with Britain we had to make things for ourselves.  Also, the British blockaded our coast so no goods could get in from other countries.  Also, the Embargo Act of 1807 prevented the U.S. from trading with foreign nations.  Because of all these factors the U.S had to produce its own goods.  When people realized we had the means to do it they realized they could profit from new industry and the industrial revolution began.
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