I Don't Remember Hearing About This in History Class

I'm no Abe Lincoln scholar, but I'm fairly certain this fact never came up in any course I've ever taken: Lincoln felt that, after emancipation, blacks ought to leave the US and settle in Central America.  In recently uncovered documents, Honest Abe says that it was "selfish" of blacks to want to stay in the US; he suggested Central America "especially because of the similarity of climate with [their] native land."

I'm not foolish enough to believe that any public figure takes even the slightest action without some ulterior motive.  I know Abe wasn't exactly a saint, but this still came as a surprise when I read the article on Yahoo!.  And that's the problem.  Apparently, historians have long been familiar with Lincoln's idea of colonization.  So why doesn't that little factoid appear in any schoolbooks?  The Civil War is one of the most significant time periods in American history.  I don't know who is to blame for this particular instance of whitewashing history, but this is ridiculous.  Students should be made aware of the entire process that led to the abolition of slavery in the United States.

Yes, it's important to contextualize Lincoln's ideas.  The idea of universal emancipation was a radical change in American society (since Americans chose to ignore that whole "all men are created equal" thing), and colonization was one solution that some people ascribed to.  There was about to be an entire nation's worth of people going from property to citizens and no one was sure how best to go about it.  Kids today should know this stuff.  Without seeing the whole picture, there can be no real understanding.

This may seem trivial, but history should be presented as it happened.  I'm not trying to demonize Lincoln, but we can't allow history to be taught selectively.