“to be the white owner of a store and keep a close watch on young black male customers because in the past you've had trouble with young black males shoplifting or holding you up. That's just being smart and protecting your property and your interests.”
I reversed the roles by asking you this:
“So then you condone the idea of me assuming you are a racist because you are a white conservative and holding that view about you, perhaps acting on it, until you prove otherwise?”
I see this as an example of painting everyone with the same brush. Keeping an eye on the kids because they are “behaving” in a way that causes concern is different than keeping an eye on them because they are black and you have had trouble with black kids. If I assume you are a racist because you are a white conservative I am also painting you with a broad brush.