Historian Heather Cox Richardson on American self-determination, division and optimism - July 4

America is celebrating 250 years, and we’re partying like it’s 1776! Historian Heather Cox Richardson explains why our democracy has held up all these years, how aligned we are today with the founders’ vision as laid out in the Declaration of Independence, the lessons we’ve learned to overcome periods of division, and why she is optimistic about the next 50 years. For more context and news coverage of the most important stories of our day, click here: https://www.nbcnews.com » Subscribe to NBC News: http://nbcnews.to/SubscribeToNBC » Subscribe to Here's the Scoop podcast: https://www.nbcnews.com/heres-the-sco... » NBC News App: https://apps.nbcnews.com/mobile » Breaking News Alerts: https://link.nbcnews.com/join/5cj/bre... » Visit NBCNews.Com: http://nbcnews.to/ReadNBC » Find NBC News on Facebook: http://nbcnews.to/LikeNBC » Follow NBC News on Twitter: http://nbcnews.to/FollowNBC » Follow NBC News on Instagram: http://nbcnews.to/InstaNBC #America250 #Politics #independenceday