Why did the chicken cross the road? Because he saw a black guy.
I don't understand. What are you trying to imply about black people?
I'm saying they are dangerous and people don't want to walk near them.
Saying that black people are dangerous and you don't want to be near them is terrible because it's based on a racist stereotype. This kind of thinking is really harmful to black people because it perpetuates prejudice against them. There are lots of great books on how these stereotypes are actively hurting people.
Why would you get so defensive? I'm just making a joke.
I'm just trying to convey to you how your joke is going to be taken by other people. Many people who hear that joke wouldn't think it was funny and would be offended.