Historical fiction vs creative nonfiction

The question came up in class about the difference between creative nonfiction and historical fiction.

Historical fiction has a setting in history, in some era or some event.  No reason why creative nonfiction cannot have the same setting.

Historical fiction may use actual historical characters.  Creative nonfiction can certainly use actual historical characters.

So, what's the difference?

All fiction, except maybe some weirdo science fiction, will have recognizable humans and settings, but that doesn't make it nonfiction.  What makes it fiction is that it has a story that derives from the writer's imagination.  Creative nonfiction can also follow a narrative arc, tell a story.  But the story it can tell is pretty strictly limited by the facts.

If Abraham Lincoln said in a letter that 'this nation is entering into dark times'--in my opinion, in creative nonfiction (other teachers will disagree) you can use that phrase as a direct quotation, as if he spoke it aloud.  You can certainly do that in historical fiction too, though in historical fiction, you're licensed to write it this way:

Lincoln slumped into his chair with a groan.  Mary said, "Tell me."

"It's hard to face; I'm not sure I can face it."

"Face what, for heavensake?"

"The dark times ahead.  This country is, it's...."  He, the great orator, simply couldn't find any more words.  He closed his mouth and stared into the fire.

You can't do that in creative nonfiction!  Too creative, too fiction-y!