Once the car is stopped, and you are no longer in danger, as much as he would deserve an ass kicking, no you couldn't legally put your hands on him....though a swift punch to the head, as long as you didn't cause physical injury, would just get you a Harrassment 2nd Degree charge here in New York State, which isn't even a crime.
Now, with saying that, even if you did hit him and injured the driver, I can't imagine any jury in the world convicting anyone for Assault after seeing that video.
Without a video you'd have a more difficult time wnning.