The worst steamboat disaster in US history occurred between Memphis and Cairo on the Mississippi on April 27, 1865, just before the end of the Civil War. This PBS show investigates three possible causes: the overloading of the boat (thousands more than the 375 occupants is was supposed to limited to, a 'torpedo' or bomb disguised as a lump of coal placed by a Confederate terrorist, or a bad boiler repair.
The overcrowding on the ship was the doing of a quartermaster officer who could have put the men (many of the passengers were former POWs returning North after being held at Andersonville, a CSA prison camp. This guy was corrupt to the core, and his Army superiors tried to get rid of him several times, but he had connections through his brother directly to Lincoln, who hired him twice and promoted him twice. The Quartermaster's brother was some sort of bigshot in the GOP.
Lincoln was assassinated and of course deified and never had to deal with his part in the deaths of around 2000 people.
http://www.pbs.org/opb/historydetectives/video/2365281276//
