What ports did the slave ships use?
The biggest and nearest. Time was of the essence in slave trading. Money was the second most important factor.
Who made money when a slave was sold to a Southerner?
The auctioneer, the ship owner and/or ship’s captain.
Why was slavery OK until the South started exporting cotton to England because of the low prices the Northern textile mills were willing to pay?
It’s not and never was OK (at least with the slave), but it existed, and still exists today, all over the world, and right under our noses.
In other words, People in the North profited from the slave trade. Now they want to condemn the South. There were slaves in the North for many years.
Cotton was the main reason for the slaves being sent to the South. The cotton was being sent to the factories in the North until the South started exporting it to Europe. Then we have a War Between the States. Nice how that works. Hypocrisy reigns supreme.