Don't be so sure that the situation in Mississippi and the rest of the South is as dire as many believe looking at this map
http://en.wikipedia.org/wiki/File:New_2000_white_percent.gif one sees that blacks instead of holding a continuos territory in the area know as "the black belt" it is an of concentration of black control counties surrounded often surrounded by White control areas. In counties (or zip codes as the map is based on) populated by more than 50% Whites, almost, undoubtedly be held by Whites during a race war. Sure a few areas will unexpectedly fall, especially, if official invite in nonwhite "refuges" and the White population don't resist which might happen in the early stages, but in some areas with less 50% Whites will come under White control by the WILL of the White population.
If we look at the situation in Mississippi, parts of eastern Arkansas and Louisiana, we see blacks surrounded with a wall of Whites to the North, West, East thought a thin wall, and south but with a possibility of using the Mississippi River delta area to reach the Gulf. Southwest and south central Arkansas and western and central Louisiana is mostly over 50% White and should allow a route to the ocean.
Unless, several counties with over 50% Whites fall or the map has change greatly in the last 12 years, possible, but unlikely to a great enough extent to matter, the corridor of White control counties will provide additional troops and supplies from northern control White areas and allow access to White control areas along the Gulf Coast.
As with cities all over the country, but on a much larger scale, a state of siege will come into play as White forces surround the Mississippi dealt area. Blacks will hold interior lines but almost undoubtedly won't have the mental prowess to use them, but Whites in the Mississippi corridor will. A similar siege will likely take place in Alabama if the Whites don't lose control of counties to the east that form a much thinner line then the White corridor in eastern Mississippi. Nonwhite controlled areas in Georgia, the Carolinas, Virginia would likely require a major offensive that would take time to prepare but the basic weaknesses of blacks would be present.
The black government would likely boil down to a bunch of black politicians, gang leaders, military officers and NCO and others declaring themselves the ruler of black America and often taking the title of Emperor. This will lead to massive gang warfare.
With blacks fighting each other, White forces on the siege line will mostly see light raids of maybe a dozens trying mostly to slip by to raid White areas, since blacks aren't generally brave enough to charge a fortified position and if they did in mass as happen at the Battle of Blood River the result would, almost undoubtedly, be the same. The black raider who manage to slip behind White lines will kill, rape and loot until stopped, and bewared cannibalism likely will become common among black forces, especially, since farms stolen from Whites will likely produce as well as the ones stolen from Whites in South Africa and Rhodesia.
Blacks, at first, will be well equipped as they loot businesses, armories, government and office buildings in their areas and the over represented blacks in support services will steal much military equipment but they won't know how to use or fix much of the equipment and when they run out of fuel they will be abandoned. The few smart black who might help will likely be kill early on as for acting White or flee. Blacks from White control areas might go to black control areas to join the looting, while Whites flee to White control areas. White Enclaves surrounded by black control areas will in time need to be evacuated to White control areas. Armed column of White refugees would likely not be attacked often.
As the race war goes on, black supplies will dwindle as they are used up or destroyed and can't be replaced. Within a year, Whites should have a full scales war machine producing supplies and well trained soldier, while blacks will have spears. This would likely be a time to reclaim Mississippi an offense should meet minimum resist but likely find widespread disease, cannibalism, starvation, a breakdown of all utilities, though if any nuclear plants fall into black areas, a some what reckless operation may have to be under taken to secure it before it melts down.
Many of the biggest problems maybe what to do with nonwhites in White areas, and nonwhite "refugees" and POWs. Also, outside intervention could be a problem with possibly Asians invading the West Coast forcing forces to have to be sent West, or Yankee invasion, though unlikely since they likely be fighting their own nonwhites, or most probably European intervention to save the "poor starving nonwhites."
What I am trying to point out is though it might be best to negotiate an peaceful arrangement with the nonwhites but at this point, they don't see that to their advantage, so Race War will likely be the result. If Race War comes, the White position even in the South is not as untenable as many believe. Whites are great warriors and producers who throughout history have defeated vast nonwhite armies even when greatly out number. Propaganda of the mainstream media shows Whites especially White males as weak and soft and as easy targets for nonwhites but White soldier make up the vast majority of elite troops in the U.S. military and kill vast numbers of nonwhites in the Zionist wars, so when White fight nonwhite oversea they are strong but when they touch US soil they become weak? Basically, blacks who need to outnumber Whites at least three to one if not more are pushed as powerful and brave. Basically, propaganda means nothing, the odds are that the White race in a Race war against the other races would prevail. Not to say that battles would not be lost but barring being attacked by our own people or treason in our leadership, the White race would prevail in a Race War.