People from Vietnam eat a lot of rice. It’s not racist to say that Vietnamese people eat a lot of rice, or that Italians really love their spaghetti, or that Japanese people like sushi.
I know if I loved watermelon I would be the first one standing in the watermelon patch during the harvest and wouldn’t care what other people think.
Most racial stereotypes boil down to simple socio-economic nose thumbing. The habits of the have-nots are mocked by the haves. Both fried chicken and watermelon were used commonly as insulting racist stereotypes in America’s racist past, often coupled with the "N" word.
Black people were not permitted to eat in most white-owned restaurants until the Civil Rights legislation of the ’60′s. When they traveled either they did not eat or carried their food with them. Fried chicken requires nothing more than a frying pan and a camp fire to cook (no oven needed). Plus chicken was cheap and readily available. Likewise, watermelon was cheap and easy to grow, so these both became known as the foods of poor people.
In addition, in the slave era, the image of a black eating those items had the implication that the items were stolen. That may have happened on farms were slaves were denied access to adequate food. The chicken and watermelon were easy to steal and were the property of the master.
Slavery was the ultimate theft of humanity, robbing a person’s freedom and control over their own lives and bodies. Those stereotype images maintained a tradition among racists, of blacks being the robbers (therefore they should be controlled, ergo: slavery is justified). It is an image that racists used to avoid thinking about the worse theft, an early example of propaganda to preserve (and then remember) the wicked institution of slavery.
If you’re really curious, you can read up on racist stereotypes to learn more.
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