Judging by Pea Ridge's posts concerning the messages and letters regarding the ships sent to Ft. Sumter, it does not look like they had that choice either. The evidence indicates Lincoln was going to have his war one way or the other.
According to you there is always a choice. Lincoln could have ignored the bombardment of Sumter. By the same token the South could have ignored the resupply of Sumter. If you want to believe that Lincoln was hell-bent on war then there is certainly more than enough evidence to suggest the Confederacy was just as eager to start it as well.