Talk it over with your wife again and KINDLY point out your concerns. Then listen to hers again. Explain that you could teach your son to punch out the other kids but this is not the correct answer.

The proper answer in my view is speak to the other parents in a kind way about your observations and ask for their suggestions regarding how they would proceed. This will give them an chance to take part in the solution. If they don't see, or wish to resolve the problem, then politely refrain from allowing your children to associate with the other children until they teach their children some manners. (The key here is be kind)

The other parents may not share your concern or even view it as a problem. The point is though "you do" and they should respect that. If they don't then you know where you stand with those parents and you have a choice to make regarding how you wish to continue the relationship. But refrain from threatening the other parents with "I will teach my son to be offensive." That will only exasperate the problem and will solve nothing.

5 grand children later and a host of other young folks hanging around thru the years has made for some interesting decision making along the way and i can tell you for sure the calm logical approach is the best way. Anyone who can't accept that approach you need to dismiss from your life. Anything else will bear nothing but bitter fruit.

Regards

__________________
"What you hear in a great jazz band is the sound of democracy. “The jazz band works best when participation is shaped by intelligent communication.”
Harmony happens whenever different parts get to form a whole by means of congruity, concord, symetry, consistency, conformity, correspondence, agreement, accord, unity, consonance…….