Scary Mike but I would have beat your ass for touching my kids. My kids don't throw tantrums. They tried it a few times when they were younger and I have simply picked them up and left with them screaming and crying. Then when they calmed down, we dealt with it and then went back. Of course, they are usually really well behaved kids and now we don't have problems as they are 11 and 8. However, if some guy had grabbed my kid like that, I would have made him regret touching another kid in that way. (It's a good thing I don't carry a gun, just saying.)
Sorry, while it probably scared the crap out of the kid, it isn't your right to deal with it. Also, you don't know what is happening. What if a kid is being beaten at home and he is reacting because of it. What you see as a tantrum could have other underlying issues. (Of course, the kid could just be a brat) I worked with kids for nearly a decade and several were at risk children in bad homes so I don't think using the threat of violence is the best option, ever. I will reprimand kids when I see them doing something and their mom or dad is doing nothing but I always revert to my teacher tone and it works immediately.
