Into new territory they acquired. They had their eyes on Cuba and parts of Mexico and Central America.
Ignoring the facts is claiming expansion of slavery was the motivation when they were content to leave with no claim upon the western territories and claiming they were leaving to protect something that wasn’t threatened anyway. Your arguments just don’t stand up.
They stand up for anyone who has done any reading on the subject.
You say they “had their eyes on” foreign territory. So what? Are you seriously trying to argue they seceded for the opportunity to spread slavery to Cuba where it already existed? Mexico where the climate for tobacco and cotton production was unsuitable? Don’t make me laugh.
The facts do indeed stand up for anybody who has read up on the subject. Slavery was not threatened in the US. Nobody fought for or against it. Both sides in this war like most wars fought over money.