The other argument I have seen a lot is that Lincoln and the dastardly Republicans want to deprive the slavers of their "property," which is a gross violation of their constitutional rights.
I have read a couple of attempts to construct a Bible based argument for slavery, but its just a mishmash that makes no sense at all.
I agree, the entire system had to corrode the values of that society.
It is sometimes alleged the Bible condones slavery, but that is a misreading.
In fact, the Bible adamantly opposes slavery for God's people, meaning in the Old Testament, the Jews.
Exodus tells us of God's freeing all Jews from slavery, and Jeremiah 34 tells us that Jews keeping Jewish slaves was the reason God destroyed the Kingdom of Judah (586 BC).
Non-Jewish slaves were to be treated justly.
Non-Jewish fugitives from slavery were to be protected, not returned.
In the New Testament Paul treats the word "slave" metaphorically, speaking of "slaves to sin", "slaves to righteousness" and "slaves to God".
Speaking more practically he says, if you are a slave, be a good slave and if a master, then treat your slave as a member of your own family.
But God is all about freeing His people from human slavery.
We see it in Exodus, in Old Testament laws and in the destruction of Judah.
The New Testament tells us that Christians are also His people, and so we can say they must not be held as, or hold other Christians as, slaves; certainly not as permanent, inheritable slaves, i.e., "property".
Yes, Bible based arguments can be made for temporary debt-slaves or indentured servants (basically contracts to pay off debts) but not for holding captive Africans as "property", especially after they converted to Christianity and so became, also, God's people.