Answer:
Europeans enslaved Africans for labor in the Americas primarily because they had already exploited and decimated Indigenous populations in the Americas, and there weren't enough Indigenous peoples available to do the work.
As European powers began to establish colonies in the Americas, they relied heavily on forced labor to extract resources and establish profitable economies. At first, they attempted to use Indigenous peoples as laborers, but these populations were quickly decimated by European diseases and forced labor, and many Indigenous peoples actively resisted enslavement and exploitation.
As a result, European powers turned to the transatlantic slave trade to obtain a steady supply of forced labor. Millions of Africans were forcibly taken from their homes and transported across the Atlantic to work on plantations and in mines in the Americas. This system of slavery was brutal and dehumanizing, and it had devastating effects on both the enslaved Africans and their descendants, as well as on the societies and economies of the Americas.