It's a little off-topic and a little cynical, but I think the larger issue here is that we've watered our teaching of history (and most things) down to soundbites and simple explanations. What we learned about Columbus, MLK, and all the founding fathers were stripped of everything controversial to create flawless heroes with views no PTA member would find offensive.
How many of the influential speeches in history have you read? I think Time's list is a good starting place. These were all inspiring, influential, and are all readily available for free:
http://content.time.com/time/specials/packages/completelist/...
If you have read even half of these, maybe then I'll buy the copyright argument.