I believe Hussein may have been right in one sense. Muslim slave traders were responsible for capturing thousands of slaves in Eastern Africa, slaves who were eventually were brought to America.
“Slavery in the Swahili Emirates of East Africa
As the primary port of call on the Swahili Coast, as well as the seat of Omani power in the region, Zanzibar
was the primary center for the slave trade in East Africa. Although the number of slaves traded in the Indian Ocean
never reached the level of the West African-Atlantic slave trade, European abolitionists focused a substantial portion
of their efforts in the 19th century on Zanzibar. It is estimated that 1.5 million slaves were exported from East Africa in the 19th century. Approximately half of them were sent to other destinations in East Africa, while the others were sent to the Indian Ocean Islands, the Middle East, India, and Brazil”
http://www.utexas.edu/cola/orgs/hemispheres/_files/pdf/slavery/Slavery_on_Swahili_Coast.pdf