In a post entitled Van Buren at Lawyers, Guns & Money, Erik Loomis refers to "a study that correctly notes the tendency of historians to give high rankings to presidents who kill a lot of Americans in wars during their tenure."
While Erik worries about more important things, such as whether this phenomenon creates an incentive for modern-day presidents to start wars, I of course am fixated on Millard Fillmore.
Millard, as you know, gets hammered as a cross between a nebbish and the anti-Christ for facilitating and signing the bills that are collectively known as the Compromise of 1850. If only he'd sabotaged the Compromise and started a war that killed as many as died starting eleven years later. Then maybe he'd be as revered as the Railsplitter!