The U.S. is a mixed bag, with laws varying greatly by state and locality.
The District of Columbia vs. Heller case, for example was triggered by the District of Columbia's refusal to allow a special police officer to keep a gun in his home, which is pretty restrictive when you think about it.
Even in states (Like mine) where it is relatively easy to purchase a firearm, it is very, very, easy to go to jail through either ignorance or stupidity.
The example you give (A traffic altercation where one or the other driver pretends to shoot) would be aggravated assault here. You don't even have to point. All you have to do is lean over and open your glove box or console in a way that suggests to the other driver you're readying a firearm.
Similarly, spoken reference to a firearm in the context of using (i.e. In a verbal confrontation) it is aggravated assualt. Pulling back your jacket to reveal that you're carrying a concealed weapon is aggravated assualt. Even touching your coat pocket in a way that suggests you have a firearm is aggravated assualt.
AA is not a minor offense in the U.S. The fines and jail time can be severe