The Battle of Chareston Harbor. What would happen if a 21st century Navy Seal appeared in 1862 Charleston AND knew what he was about to do would not affect his time line? All the parts of the book are historical possibilities. The Seal only introduces items already invented or would be invented before 1870. This is part of the histrical fact the South lead the way in inventions during the war. What might have happen if the South had had some luck?