There were two things my parents told me repeatedly when I was a boy: One, I would have to work harder than white kids to get ahead in life, and two, when out and about, I would have to do everything I could to avoid confrontations with police officers and white strangers. As for the first thing, I recall asking my parents exactly how much more did I have to work, and being told double, at the minimum. (This meant no comic books, no video games, no TV—I was only allowed to watch PBS.) As for the second thing, it really meant never letting down my fear of white police officers or loud/angry white men. This was 30 years ago, and my family was not poor and didn't live in a ghetto. We stayed in a leafy and quiet section of our medium-sized American city, I attended a good school, and my best friend was Toufik, an Iraqi whose father managed an oil company. But even living in this seemingly sheltered segment of society was not enough to protect me, a black boy, from the realities of American racism.

My parents went to great lengths to fix in my head a permanent and realistic picture of this society. They wanted me to forget about American laws, about my rights, and about what people in the news, in school, and in books said about the fairness of the justice system, and instead just focus on the facts—who gets arrested, who ends up in prison, who is on death row, and who ends up dead. My chances of surviving this brutal system and of getting to college would be greatly improved if I always operated with an understanding of what America really is and not what America thinks or imagines it is. When in the classroom, I had to see the white teacher as a person who was expecting me to fail and drop out. And when walking or riding home, I had to be aware that my skin (not what I wore, did, or said) coded me as a criminal.

When we moved back to Zimbabwe in 1981, my parents stopped warning me about bad white people and also allowed me to watch as much TV as I wanted (though there was only one channel and it operated only seven hours a day—from 5 p.m. to midnight). It was such a relief to be in Zimbabwe. I was allowed to get a C without having to fear that my future was irrevocably ruined, that some racist teacher would send me to special ed. I was allowed to ride my bike around town without thinking about what my skin might mean to this or that person. I could finally be normal and make normal mistakes. If I was caught breaking the law (shoplifting, smoking pot, buying booze or cigarettes with money I nicked from my mother's purse, or driving the car without a license), I would not be seen as a criminal but as a teenager.

Thirty years later, I find myself with a teenage son. We live in an American city. He is in high school. He is black and tall. He likes to jog and hang out with friends. He seems to be having a happy childhood. He plans to go to college. All seemed to be going well until George Zimmerman was acquitted for killing an unarmed teenager, Trayvon Martin. Now, I don't want to go over the tedious details and arguments of this case. I just want to point out two clear facts: One, had Trayvon Martin been white, he would have made it home alive. The second fact: George Zimmerman is not going to jail. These two facts mean one thing: Little has changed from the days when my parents warned me about cops and aggressive white men. And because there has been little change, it would be foolish, even negligent, of me not to impress upon my son a hard understanding of the society he lives in.

This is what I told him over dinner recently: The most important thing to know is that your rights are useless to you if you are dead. So when it comes down to reality, forget about them. If a cop approaches you for some reason or another, be cool and diffident. Even if the cop is an asshole, even if he is totally wrong, do not raise your voice or challenge him in any way. I know, it sucks—but, as I said, the name of the game is staying alive. Also, if a white man asks what you are doing in this or that neighborhood, don't say: You have no right to ask me that. Why? Because your rights mean jack when you are dead. So be calm, do not make sudden moves, answer his questions as clearly as possible, and always keep your hands visible. (Once, when two cops approached me with drawn guns and demanded to see my ID, I, with raised hands, calmly told them that it was in my back pocket, but I feared lowering my hands. Once they understood that I was not challenging their power to take my life, the tension dropped and one of the cops searched my pockets for and found my ID—I was not the black guy they were looking for. I lived to tell that story.)

So never get angry, keep the situation cool, and always be aware of the color of your skin when you are jogging to Lake Washington or to the soccer field. Know that what many people see is not a teenager enjoying the day, but just a criminal, someone who should be locked up, someone who is a menace to society. I do not want a dead son.