Still, violence has been the answer in many (most?) political revolutions, including the American revolution and separation from Britain.
The Confederacy tried to replace their Constitutional government and the policies instituted by the leaders elected by the people with a violence-enforced new state inside the territory of their existing one and got (justifiably) multi-generationally brutalized for their trouble. The town I grew up in and moved away from was still raising funds to rebuild some of the places that were burned to the ground in the war. That was fundraising in the 1980s.
Every time someone points to the 1776 war as a success story I feel compelled to point out that half the descendants of that war's victors tried a very similar thing in 1861 to absolutely ruinous result.
(On this topic: Fort Sumter is an interesting story. While it was never taken during the war, it basically became a target-practice and weapons field-test location for the Union navy: every time they had a new technique or a new cannon they wanted to try out, they'd try it on the fort. By the end of the war, the fort was "standing" only in the sense that the bulk of its above-ground works had been blasted flat and were shoved together into an earthworks bunker; the Confederates were basically sheltering in a hole that a lobbed shell could fall into at any time.
And while the fort and its northways sister kept Union ships out of the harbor, it didn't stop them from firing past the fort into Charleston itself, since "war crimes" and "civilian populations" weren't really a concept yet.
People very much went into that war thinking there wouldn't be consequences for ordinary folk. They were very much wrong.)
Once that happened, it really wasn't up to Congress or the President any longer. The capture of Fort Sumter and declaration of succession moved the conversation from "How much slavery can America tolerate" to "this insurgent government has stolen half of the country's territory." The response to that threat was as self-evident as it would have been if that territory had been taken by another existing nation.
It is strange to me that you take such a fatalistic approach to history, where nothing else was ever possible.
of course at some point there is no turning back, particularly after the deed is done.
If nothing else is possible, what does that say about the current state and our choices about our future? what will be will be? might as well stay home watching netflix and see what happens?
As an example to illustrate your definition, do you believe that it was possible to find peace with Hitler and Nazi Germany without having to fight WWII in Europe?
I'll express my answer on the American civil war with the framing of your definition of 'fatalistic approach to history'.