If we were to follow your logic, then we should remove all historical monuments, not just the monuments you dislike.  What's worse is that many of the books which taught you about that period have distorted that facts in favor of an incorrect political correctness.  While the south wanted to sustain slavery, the war was actually about states-rights and the right of the U.S. Government to impose its will upon the southern states.  There were many issues such as (Tariffs)along with slavery which were the driving forces behind the secession of the south.