This is not the first time our president has needed a history lesson on the Civil War.
It also happened in May 1865, when the war was as fresh as cavalry dust and the Yankees were still chasing the fugitive Confederate president Jefferson Davis across Georgia.
Here's a link to our original story in The Stoneman Gazette, where Union Gen. William Palmer wrote a passionate and eloquent letter intended for new President Andrew Johnson. Palmer was alarmed by reports that the adminstration might delay the full emancipation of slaves, now that Lincoln was dead. Gen. Palmer wanted to set the president straight about what he was hearing from Southerners and how emancipation was non-negotiable.
Our story also includes links to the "Declaration of Causes," where several seceding states explained why they left the Union.
If you have any questions about the real reasons for the Civil War, it's worth revisiting.