Missing the point like that doesn't exactly make you a genius either.
Just why somebody's great-grandfather or great-great-grandfather went to war doesn't say much about why war broke out.
Slaveowners saw slavery as threatened by Republicans' electoral victory, so they tried to take their states outside the union.
The way they did that -- without approval from the Congress and with the formation of a new country and violence -- meant war, unless the federal government was exceptionally spineless.
I guess if nobody went, you wouldn't have had a war, so individual motivations are contributory factors, but there was a war before most people's ancestors had any say or made any decisions.
As I wrote before: slavery was more secure in 1861 than it had been for a decade. The Corwin Amendment had passed Congress, the Dred Scott Decision was the law of the land, Lincoln was a minority president presiding over a divided country with a bankrupt treasury.
Lincoln would compromise backwards and forwards over slavery, as the issue in itself was not one that stirred the masses of the North; but he could not compromise over two things: repealing the Morrill Tariff and allowing the mouth of the Mississippi River to fall under the control of a foreign power.
That Southerners saw slavery as being threatened by the Republicans is a given. But that in itself was not enough to sever the Union. The Morrill Tariff could, as it would protect northern industry and 3/4 of the revenue collected would come from the South.
The causes of the Civil War are complicated and to reduce them to the simplicity of a single cause (slavery) that was not a major issue in 1861 is foolish beyond belief.