UPDATE: Be sure to read ZouDave's comment below.
I figured now was a good time to introduce history lessons into the story. Here is a great (and lengthy) write-up about Bleeding Kansas and the Missouri Civil War. It article manages to prove two things:
a) While many (but not all) of the Missourians involved in the war were on the horrifically wrong side of history, neither side's hands were clean; and
b) Missourians have always been prone to battle each other. As a quick perusal of message boards has always shown, the only people Missourians hate more than non-Missourians are fellow Missourians. Good times.
[W]hen doing an internet search, you will get a very different story when searching for "Bleeding Kansas" than you will get if you search on "Missouri Civil War." Many of the books that are available are no different. Though most lean toward the Kansas side of the conflict due to its anti-slavery sentiment, Missouri cannot be ignored in its contribution to history and its heavy losses during the Civil War. Officially, a Union State, Missouri was internally divided between its pro-slavery sentiments and its obligation as a Union State. Never officially entering the Civil War, Missouri fought its own internal battles between the Federal Officers and its own State Forces.
Even when we visit the historical sites of Kansas and Missouri, we get a different impression in the "telling." Kansas sites will focus on the great battle of Mine Creek, where the Union Forces won the skirmish against the Confederates at immense odds; the Lawrence Massacre by Quantrill's Raiders, or, upon John Brown, the fanatic abolitionist, and his actions to defeat the Missouri Bushwhackers.
In Missouri we heard the stories of the burning of Osceola by Lane's Kansas Brigade, the attack upon the Missouri building that killed many innocent women and children, and the forcible evacuation of Kansas City area counties that displaced many Missourians and turned the area into a desolate "No Mans Land."
The "war" between Kansas and Missouri began almost immediately when Kansas was opened for settlement in 1854, seven years before the Civil War officially began. No doubt, both sides were ugly -- it was a "war" between people that had strong opposing sentiments and lifestyles at stake.
Who says sports blogs can't teach you something? As you read all the way through this, you learn a lot about some of the heroes that kept Missouri a Union state, too, which is nice and reassuring. However, along with the heroes, the Union had its share of villains too (as tends to happen during war).
And as you read this, you can start to see where this changed from "abolition vs slavery" to "Kansas vs Missouri".
Click 'Full Story' for more.
You really need to read it all, but here's an extended excerpt.
Yet another skirmish between Missouri State and Federal forces occurred at the Battle of Booneville on June 17th, 1861, when Captain Lyon was intent upon putting down Jacksons’ State Guard. As the guard retreated towards Boonville, Lyon embarked on steamboats, transported his men to below Boonville, marched to the town, and engaged the enemy. In a short fight, Lyon dispersed the Confederates, and occupied Boonville. This early victory established Union control of the Missouri River and helped douse attempts to place Missouri in the Confederacy.
In the summer of 1861, Kansas Senator James H. Lane returned to his home state to command what was called "Lane's Brigade."
Supposedly composed of Kansas infantry and cavalry, the force was more akin to a ruthless band of Jayhawkers wearing United States uniforms. His antics, as he rampaged through Missouri, would earn him the nickname of the "Grim Chieftain" for the death and destruction he brought on the people of Missouri.
In September of 1861 Lane’s Brigade descended on the town of Osceola, Missouri. When Lane's troops found a cache of Confederate military supplies in the town, Lane decided to wipe Osceola from the map.
First, Osceola was stripped of all of its valuable goods which were loaded into wagons taken from the townspeople. Then, nine citizens were given a farcical trial and shot. Finally, Lane's men brought their frenzy of pillaging and murder to a close by burning the entire town. The settlement suffered more than $1,000,000 worth of damage including that belonging to pro-Union citizens.
In 1862, Quantrill began his infamous raiding career in western Missouri and then across the border into Kansas by plundering the towns of Olathe, Spring Hill and Shawnee. His raids gained the attention of other desperados. By 1863, Quantrill recruited others who joined his company including "Bloody" Bill Anderson and Frank and Jesse James.
...
In an effort to destroy the guerrillas' base of support, Union troops began to arrest Kansas City area women in July, 1863, who were were providing support for the bushwhackers or suspected of gathering information on the partisans' behalf. Of particular interest to the Federal Troops were the known relatives of the Border Ruffians, including family members of "Bloody Bill" Anderson and the Younger Brothers. Detaining them in several buildings throughout the Kansas City area, women and children were detained until they could be transported out of the area and tried. Overcrowded and invested with rats and vermin of all kinds, the women and children housed in these buildings suffered inexplicably.
One such dilapidated three story building in downtown Kansas City was in very poor condition, with a weak foundation and plaster constantly falling from the walls and ceilings. Though signs that it was unstable were taken note of, such as large cracks in the walls and ceilings, and large amounts of mortar dust on the floor, the signs were ignored. On August 13, 1863, the building collapsed killing 5 women and injuring dozens of others.
Among the killed and injured in the collapse were women who were close relatives of prominent Confederate guerrillas. Those killed in the collapse, included Josephine Anderson, sister of "Bloody Bill Anderson", Susan Crawford Vandever and Armenia Crawford Selvey, Cole Younger's cousins, Charity McCorkle Kerr, wife to Quantrillian member Nathan Kerr, and a woman named Mrs. Wilson. Many others were injured and scarred. Caroline Younger, sister to Cole and James Younger, would die two years later as a result of her injuries. Another Anderson sister was crippled for life, when both of her legs were broken in the incident.
When news of the collapse reached the families of the dead and injured, they went wild. Soon crowds began to gather around the ruins as the dead and wounded were carried off, shouting "Murder!" at the Union forces. Just four days later on August 18, 1863, General Ewing issued General Order Number 10, which "officially" stated that any person - man, woman or child, who was directly involved with aiding a band of guerrillas would be jailed.
Later, Quantrill and his men would claim that the building was deliberately weakened, giving them ammunition for the infamous attack on Lawrence that was about to come.
Lawrence was a town long hated by Quantrill and his men. Home of the demagogic antislavery Senator, Jim Lane, it was also a stronghold of the Red Legs, Union guerrillas who had sacked much of western Missouri. An attack on this citadel of abolition would bring revenge for any wrongs, real or imagined, that the Southerners had suffered.
Early on the morning of August 21, 1863, Quantrill, along with his murderous force of about 400, descended on the still sleeping town of Lawrence. Incensed by the free-state headquarters town, Quantrill set out on his revenge against the Jayhawker community. In this carefully orchestrated early morning raid he and his band, in four terrible hours, turned the town into a bloody and blazing inferno unparallel in its brutality.

So here's my question: how many women and children have died at the hands of the Duke-UNC rivalry? Michigan-Ohio State? USC-UCLA? How many rivalries celebrate the deaths in a T-shirt? That's what I thought. As I've already said multiple times, the nation has no idea what it's in for with this rivalry...