Because The purpose of the Reconstruction was to help the South become a part of the Union again. Federal troops occupied much of the South during the Reconstruction to insure that laws were followed and that another uprising did not occur. Many people wanted the South to be punished for trying to leave the Union. So if something Breaks apart I know It can be put back together again.
The states were all trying to create their own government and all the other nations were confused as to who wanted what in trade or how anything worked