Harriet Tubman was the most famous conductor on the Underground Railroad. She seized her own freedom and then led many more American slaves to theirs. What you might not know is that Harriet also taught entrepreneurship classes to freed slaves to help them start businesses. She also was a spy for the Union army and helped plan a major military operation that freed 700 American slaves by force. She is a hero of the Second American Revolution -- the war that ended American slavery and that made American capitalism possible.