[smug]

the south labored under their misconception that they actions were legal

The south knew that in the grand skim of things their actions were legal (if they won), but they had no misgivings that the North would think differently. Just as the North were sure that they were not Cromwell's Miscreant's

[Non-Sequitur]

The south knew that in the grand skim of things their actions were legal (if they won), but they had no misgivings that the North would think differently.

And in the grand scheme of things it turned out they were wrong.