Can a police officer arrest you for laying on your horn in traffic?

While I was stuck in traffic today, I laid on my horn as someone cut me off very fast. A police officer then jumps out of his car (in the next lane) ran over to my car and started pounding on my hood and windows saying "WHO' LAYING ON THE HORN" He attempted to open my drivers door and pull me out of the car. I rolled down my windows a little bit and he said he should take me in for "public disturbance" He gave me a few warning lines, and walked back into the traffic and disappeared. I'm totally confused at this point, is this even legal?????