I have to disagree with part of the premise. While the speech is copyrighted, that might not be the reason most people haven't read or seen the entirety of the speech. If schools really wanted to teach it, it would be well within fair use laws for them to show the whole thing. There are probably a variety of other reasons why you don't see this speech taught in schools.
First one that comes to mind is its length. Unlike the Gettysburg Address, this isn't some short speech that could be easily recited from memory.
Secondly, there is a lot of religious imagery in the speech. I could certainly imagine people objecting to having the speech presented in a secular school.
Finally and probably most importantly, what do speeches really teach us? They aren't particularly valuable outside of context. How many of the speeches listed here (http://www.americanrhetoric.com/top100speechesall.html) are really taught in school?
First one that comes to mind is its length. Unlike the Gettysburg Address, this isn't some short speech that could be easily recited from memory.
Secondly, there is a lot of religious imagery in the speech. I could certainly imagine people objecting to having the speech presented in a secular school.
Finally and probably most importantly, what do speeches really teach us? They aren't particularly valuable outside of context. How many of the speeches listed here (http://www.americanrhetoric.com/top100speechesall.html) are really taught in school?