“The political and societal will to use brute force against a peaceful political process does not exist in our time.”
Hmmm, its just my opinion against yours, so no point arguing. However, you and I have very different opinions as to the nature of the people who rule us and what they will do to retain power.
You seem like a smart chap. When you get a moment, stop and think your way through the basic component steps of secession by one or more states, with an emphasis toward the actions and reactions of both sides.
If you plot out how such a thing would unfold, using reason and logic, I think you'll agree that military retaliation against the secessionist states is unlikely.