The transportation revolution was not as important in the south as it was in the north because:

During these years, the North and the South had very different economies. While the North had a more industrial and commercial economy, the South remained an agricultural and mostly rural area. The transportation revolution allowed the North to be better connected with suppliers and consumers. It also allowed it to easily transport materials, resources and goods. On the other hand, this was less important for the South, as most farmers remained reasonably close to their land all the time, and had little need for very efficient transportation.

c) troops march forward in close formation against newer, more accurate weapons