Irin,
I am not sure where to start, as I usually engage in debate type formats. I am not sure wht you have read or where you really want to start.. That being the case lets start off with one source that I think is very important to the issue --James Buchanan. I suggest reading--
Mr. Buchanan's Administration on the Eve of the Rebellion. Pages 162- 230
Publication info--
Book Title: Mr. Buchanan's Administration on the Eve of the Rebellion. Contributors: James Buchanan - author. Publisher: D. Appleton. Place of Publication: New York. Publication Year: 1866.
This is an online publication, but I have posted this also in SHAPE website at http://southernheritageadvancementpreservationeducation.com/e107_plugins/forum/forum_viewtopic.php?2009189.post
There is tremendous amount of info in this book. I would suggest you make notes for your use.
I really do better when someone plays the devils advocate so feel free to push me for answers.
George