What then did Browns raid really accomplish?
A. We can only guess. As I see it, one immediate affect of the raid was that southern militia companies who never took their military drill very seriously suddenly got a wake up call. They drilled with a lot more proficiency after the raid out of a perceived necessity. That being the case, it can be argued that, without the raid, when the war finally came, the southern army would have collapsed right away. But as it turned out, the better drilled southern soldiers led by officers who had experience leading men into battle in the Mexican War (northern generals had little or no such experience at the beginning of the war) were able to win many victories and keep the war going for four years. Given Lincolns reluctance to free the slaves, it is doubtful that Lincoln would ever have considered freeing them at all if the war had been any shorter.