We have lived for some time under a dictatorship of thought called "The Inevitability of War" which, in the previous generation, overthrew an historiography called "the Blundering Generation." Under "Blundering" the question is naturally which decisions precipitated war. Under the "Inevitables" it's all moot.
The revisionists Inevitables, headed by James McPherson, have run a tight ship and there has been precious little serious public discussion about choices that caused war. I believe Edward Ayers to be the highest-stature scholarly "Blunderer" operating today. Here he is joined by what must be the highest stature pop historian in the same camp. Good luck to them both because "inevitability" is not an historical concept and those reasonable questions about the Civil War are which decisions triggered events not whether decisions triggered them.
(That's Marvel, top right.)