I’m not sure that we are very far apart in our contentions. You state that, based on Lincoln’s Inaugural Address that Lincoln did not intend to go to war, until or unless the Confederacy started it, and that he intended to continue Buchanan’s policies of supporting the Union forts, and maintain the functions of the Federal Government. I really don’t disagree with this, as far as it goes.
My contention is that war was essentially inevitable, given that the seceding states would not allow him to support the US Troops in Forts throughout the South, nor to collect import duties. So, Lincoln was not for war unless the Confederacy started it, but if he attempted to resupply and reinforce the Forts, they were going to start it. In fact, it ws important for public support that they be seen to start it. Fortunately, Davis, Pickens, and Beauregard obliged him.
There, fixed it for you. ;-)