Slavery was the underlined cause of the war. Lost cause believers and revisionists will deny that but the maine cause the the riff between North and South was the slavery question.
http://rationalwiki.org/wiki/Historical_revisionism
http://www.princeton.edu/~achaney/tmve/wiki100k/docs/Historical_revisionism_(negationism).html
Not all historical revisionism is bad, Millander. I earnestly believe that we do need to look over the events and underlying causes of the American Civil War in light of new knowledge of the period and to do so in an unbiased manner.
It's incredibly important to note that the Civil War was not blatantly about slavery at the onset. I'm sure you realize that the Civil War essentially began with the Battle of Fort Sumter (1861), when the Confederate troops under Beauregard began to shell the fort. This leads one to suspect that the war was not begun for slavery, but as an independence movement.
It is a shame that so many deny the large estrangement that resulted over the slavery question, so large that it ruptured the nation into two separate states (or one, depending on your viewpoint). The North and South had different opinions on slavery, but this did not result in war independently of any other factors. Even Lincoln is quoted to have said "My paramount object in this struggle is to save the Union, and is not either to save or to destroy slavery. If I could save the Union without freeing any slave I would do it, and if I could save it by freeing all the slaves I would do it; and if I could save it by freeing some and leaving others alone I would also do that" in a letter to Horace Greeley in 1862.
It is also important to note that the Emancipation Proclamation of 1863 did not end slavery in the Union, and would only apply to states "still in revolt". This meant that slavery in the border states was preserved in the border states until slavery was officially abolished (13th Amendment, 1865-Post Civil War).
The greatest factor in the American Civil War would be the preservation of the Union as a single nation as opposed to different nations. When the Confederacy formed, Fort Sumter (in SC) was not evacuated by the Union troops, essentially indicating that the Confederate government was not recognized as a legitimate body (France nor Britain recognized them either). Following the shelling of Ft. Sumter, the southern states were considered to be "in revolt" and responded to accordingly.
The American Civil War was more the result of estrangement caused by sectionalism than motivated by slavery alone. Slavery was a factor, but to call it the cause of the American Civil War is a logical fallacy.
Sources:
http://www.civilwar.org/battlefields/fort-sumter.html?tab=facts
http://www.abrahamlincolnonline.org/lincoln/speeches/greeley.htm
http://www.archives.gov/exhibits/featured_documents/emancipation_proclamation/
PS: I've always liked the Union. 
Well said, I was going to write an explanation about the circumstances that underlined, evovled, rose, and fell during the war. However I feel that you have done a good job at describing the cirumstances.
On another note, the moment that I saw the title for this thread I knew imediatly that there would be pages of "The war was all about slavery!" folowed by "No it was not!" etc.
* However, while I feel that while this is an un-avoidable topic with anything covering this war, I feel that we have digresed from the origional intention of this thread, to tell which side you look foreward to play as the most. Obviously it is up to the admins in the end, yet I almost think that there should be a special thread for such debate. And I specifically use the term "debate" to note that I do not invision a thread full of "You racist slavers!" and "You union loving oppresors!" etc.
Yes, I know that is is near impossible to avoid the quickly writen retaliatory comments of many people. That wisthstanding, I mean for a thread to allow for such things as the post I have quoted, Well thought out, researched, and CITED arguements from both sides. So while the unnecissary comments will arise, I would hope that a format of more educated communication would dishearten the casual comentor from whimsical posts. (I realizes this is most likley an un-realistic expectaion, However it is one I would be proud to see this community acomplish)
With all said, I am currently finished (For now) with offering up my opinion on this matter, and shall leave the rest to a mature admin panel, community, and developers. I wish a good day to you all.
Foot Notes:
*(The war initiated over states rights to secede)
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