Was slavery all about racism?

I do not think that slavery was all about racism. It was also very much about economics. But I think it was far more complicated than two sentences can make clear.  Let me see if I can talk us through this to share my thoughts.

Racism is the perception that those of another race are inferior in some way and should be treated thus.  Those who participated in the slave trade found it easier to enslave Africans because they were of another race, had cultures that superficially seemed inferior to European or American culture, and of course, had few defenses against the invaders. These people were "the other," and as such, there was no need to treat them as fully human, a rationale in their minds for treating them no differently than beasts of burden. If we want to enslave a people and treat them like animals, it seems to salve our consciences to say they are another race, so somehow it doesn't count.  While it is impossible for me to see all of this through the eyes of an early slave trader or plantation owner, I do know it is always easier to demonize people whom we want to use for our own purposes or whom we want to brutalize, so that we can convince ourselves we are still good people.  In general I would say that racism made it easier for white people to enslave Africans than had they wanted to enslave people who looked like them.

However, money is a powerful motivator, and slavery is what built the American South into an agricultural powerhouse in its day.  It is hard to picture this today, but think about how much money a company could make if it didn't have to pay any of its workers!  Even if it had to shelter, clothe, and feed them, it would still come out ahead, if it did as the plantation owners did, spending as little as possible on any of their needs. Free labor is what the plantation owners had, as well as the offspring of slaves, who could be sold or become more free labor, the "interest" on their investment. I would say that had someone discovered a civilization of white people who could have been enslaved, we would still have had slavery, although people's consciences might have troubled them just a little as they deposited all their money in the bank.