Fantasy is the notion that a Nation founded on the God given principle of Independence, should think it appropriate to fight against other people's right to Independence.
Cosmopolitan elites like to kid themselves about their love of universal rights and the common good, but it is total nonsense. Just take a look at their strongholds. These people talk like MLK, but they live like the KKK or like a KKK fantasy world. Our elites live in hyper-white exclusive communities. Many are gated and walled. Often, they have their own private security forces. A modern college community, for example, operates almost like an autonomous zone with their own government and police.
But your very definition is a fantasy.
The United States went to war in 1861 to defeat the military power that threatened it, assaulted it and declared war on it.
So "independence" alone did not and could not start war.
Military actions could and did.
No, fantasy is the notion that Confederate military force which first provoked war, then started war and formally declared war on the United States, while supporting pro-Confederates in Union states, and then refused to seek peace on any terms short of "unconditional surrender" -- only fantasy could suggest that those Confederates were anything other than politically insane.