Lincoln Waged War on Half the Country?

I've been trying to understand this whole tea party movement thing. I don't think I'll ever be successful in that project.

Short version of the story: I found this website, which led me to a story (linked below) with this quote:

"The president who had the least fidelity to the Constitution was Abraham Lincoln, who waged war on half the country, even though there's obviously no authority for that, a war that killed nearly 700,000 people. President Obama is close to that end of lacking fidelity to the Constitution."

-author and judicial analyst Andrew P. Napolitano

Lincoln the war-wager, eh? Not the man who said "A house divided against itself cannot stand."