I was walking through Dupont Circle, thinking about acid rain, if you want to know the truth, when a guy walked up and offered to sell me some drugs.

His body language was pretty remarkable, given his product. He didn't sidle or sneak. He didn't look around for cops before springing his proposal -- as well he might have, since there were cops in plain view, and since I might have been one myself.

He simply sauntered up beside me, looked straight into my baby blues and said:

"Hey, you want to buy some stuff?"

My first reaction was that he must be a Rent-a-Prankster, sicked on me by friends who were doubtless hiding behind one of the nearby trees and laughing themselves silly. After all, I looked more like a diplomat than a druggie, clad as I was in a gray suit, a white shirt, a modest patterned tie and shoes that had been shined that very afternoon.

The reporter in me made me ask the guy: "What kind of stuff?"

"Grass. Good stuff," he said.

"No, thanks, I don't think so," I replied.

He nodded, and reversed direction. The whole encounter took about six seconds. When I reached the other side of the circle, I looked back into the crowd on the benches to see if I could spot him. There he was, over by the chess tables, reading a magazine.

This happened nearly a week ago as I write this. Ever since, I've been trying to sort out my feelings about it. Here's where I come down:

I'm angry.

I'm angry that a guy can walk up and offer drugs to somebody in broad daylight and not show the slightest worry about being caught.

I'm angry at myself for not telling a cop what had just happened. The truth was, I was late for an appointment, and I decided that being on time was more important than turning in some small-time marijuana dealer.

I'm angry at myself for saying "thanks" to the guy. It was a reflex. But that's just the trouble. I treated a drug dealer the way I would have treated a salesman at a men's clothing store. I essentially told a criminal, "Thanks, just looking."

But most of all, I'm angry that this guy has -- and had, and will have -- customers. Five dollars would buy you several marijuana cigarettes from the Dupont Circle dealer. But the same $5 would buy a street person a couple of meals, or help the heart fund, or pay for a phone call to your ailing aunt in Ohio. I've never seen the world become a better place because someone spent $5 on dope, and I never expect to. So why do people do it?

Just as red-light runners and litterbugs never mend their ways because of newspaper columns, I hardly expect the Dupont Circle dealer to start studying for the priesthood because of what I've written here. But we, his potential customers, can do better than I did the other day. Don't look the other way. Don't say thanks. And whatever you do, don't buy.