The first rule of driving is this: drive safely. If you think you can maneuver safely in traffic, do so. Otherwise, sit still or step out from behind the steering wheel. Our reflexes and skills vary, and drivers must understand and accommodate that when they operate their own vehicles.
Too many drivers ignore that rule, or they expect other drivers to have their "skill" or daring attitude. They try to encourage hesitant drivers with the horn.
Now, sometimes, a tootle of the horn is what you need: you are looking at something other than your path and the green light has been burning daylight for a good five or more seconds. A short "wake-up" beep does the trick: drivers look up, gasp, engage the car and wave (all fingers!) at the driver who alerted them. It happens to everyone, amateurs and pros alike.
Some days, it's just a tootle and both drivers are civil. Alas, too often lately are drivers anything but. Recently, an acquaintance died after an encounter with a fellow driver, who is accused of following him into a parking lot and committing violence against him. Shocking — but not really.
I had a front seat to road rage about a decade ago. I don't remember if my driver didn't accelerate quickly enough, or someone changed lanes too closely. What I do remember is the rude gesture of my driver. I do remember the furious encounter after the other driver followed my car to its destination. Both drivers dwarfed me in size, so I couldn't safely separate them. I was frightened and furious, and I walked away from the screaming drivers.
I was lucky. I got out with my life. So did my driver. Our friendship, however, was a victim of this incident; my driver didn't understand the danger his actions posed.
This morning, I was on the first of two major roads I travel to work. I had to turn left across oncoming traffic, and I saw a gap in traffic. Could I cross safely? I wasn't sure, so I waited. I heard a long honk, not a tootle. I kept waiting. Five seconds later, the gap was unmistakably safe, so I proceeded — and wondered if the angry honker would pursue me to "teach me a lesson."
Thankfully, no one followed me. Today I was lucky. Tomorrow, my caution may be someone else's flashpoint. Let's hope you and I never find out.