If that is your argument, then you need to shut up about any other rational.
If you truly believe that power is the only deciding factor, you have no business debating the topic. Why don't you save both you and us a lot of time and come down on one side or the other.
If in your opinion, *POWER* is not the deciding factor, then shut up about it. Stop putting it forward as your argument.
It was Lincoln who made the argument and Williams who ratified it. But, it's really just common sense. Anyone who tries to replace an existing government should expect a fight. Our Founding Fathers, all of them grownups, understood that fact of life and that is why they pledged their lives, their fortunes and their sacred honor. They expected a fight and they got one. In the end, they prevailed. But, each of them understood what was at stake. None of them were shocked to learn that the British sent more troops.
The Southern secessionists were just very lucky that it was Lincoln and not Andrew Jackson (a Southerner) who was president. Jackson probably would have hung all of the secessionist leaders after very brief trials. That's the usual price one pays for failing at the game of revolution, secession, rebellion, coup d'etat or whatever other label you want to use to describe this kind of power play. It's always been risky to try to replace an existing government.
I don't know how you can rationally think about replacing governments without confronting questions of power. Greater power is what the Southern secessionists were seeking. I want to think that you understand that reality.