Why are there so many black people in America? Are they all left by former slaves?

Slavers set out from Europe and arrived in Africa by boat. After they captured blacks in Africa by various despicable means, they shipped slaves to the United States, sold them to American planters, and then shipped American gold and industrial raw materials back to Europe. This is the so-called triangle trade. The Portuguese started the slave trade first, but the British came from behind and became the main operator of triangle trade. One day, in the vast and lonely Atlantic Ocean, who was driving the pirate ship? What are they going to do? It turned out that this was a "slave hunting team" organized by European colonists. "Gold Coast" and "Slave Coast" are the main places for their activities. At first, they attacked African black villages, burned down houses and took away lean men. This criminal activity of plundering directly by force has aroused fierce resistance from the African people. So they changed their strategy. They shot and incited some African chiefs to engage in slave hunting. Then they used small commodities such as guns, ammunition, liqueur and textiles to buy blacks from chiefs and sell them as slaves. In this way, slave hunting activities not only spread all over the coast of Africa, but also went deep into the mainland, causing more serious damage to Africa. On the coast of Africa, European colonists built forts and commercial stations. The captured blacks were sent to the slave market in strings for the slave traders to "buy". After the buyer and the seller made the final decision, the slaver branded the arms and chests of the slaves with a red-hot iron. Then these slaves were locked in the dungeons of fortresses and commercial stations. When they were full, they were driven aboard and shipped to America. The slaves were shipped to the United States and then shipped to the slave market for American planters to buy.