yes the difference is you are mature enough to control yourself, and the child is not. I understand that. No one is saying to stand around and let it happen, but imagine if one day you have a child who DOES go through that stage - how would you feel if everyone went around protecting their child to the point no one would play with your child anymore? I can understand if its over the top ongoing aggression to say nicely to the mother (no need to hurt feelings just for the sake of it) "I love spending time with you, but I don't think our kids are a good match for playmates right now. Maybe just you and I can get together without the kids sometime" or something like that. I however, understand aggression comes with the toddler territory. My oldest NEVER hit anyone until starting school. Then he saw the aggression and started doing it occasionally too, though nothing like my aggressive child. I am glad I didn't act all high and mighty because I'd be feeling like quite the fool right now! (not saying you are, just saying its tempting to do so when you have a non-aggressive child, to think "oh I must have done something to create this non aggressive child" when really the credit just goes to the childs temperment - which is why the same parent can raise children who never aggress and children who do) Anyway, you don't have to stand around and watch, but you can try being "in the middle" of the play (this works the best for me, we play games where the adult is the center of the game, and it eliminates aggression for some reason). This way the children can learn to play together, you can prevent injury, you dont have to hurt the other child emotionally to protect your child physically, etc. It's win/win. You wouldnt want someone to hurt your child emotionally just to protect their physically either I'm sure, if the situation were reversed, which I hope for your sake that it never is, because I find its must easier to be the parent of the non-aggressor then it is to be the parent of the aggressor.
Anytime you are moved to anger like that though, it IS worth exploring. As those are human feelings, it's also human to sometimes slip a little in the control of those feelings. So I personally wouldn't just say "I have every right to be so mad I want to hurt them, because I wouldnt actually do it" to be on the safe side, I personally would say "why am I THIS mad about this? Of course I dont want to see my child be hurt, but should I feel like hurting another person, a child, even if I wouldnt act on it? What is causing such extreme emotions in me?" etc, and I'd work on it, and try to bring myself down so that eventually I could respond to the situation effectively without boiling anger and desire to hurt someone elses child. I ask myself how I could feel if the situation was reversed. I would ask myself how my child could BENEFIT from the situation. I would take the opportunity to teach my child how they can protect themselves (without hitting back) help them learn when their playmate is getting to "that point" so they can walk away etc. So many skills can be learned in these situations that will prepare them for when we wont be there. I understand some people feel a certain age is too young to learn these things, but I dont think a child is ever to young to learn how to protect themselves without hurting others, and this is something we teach to one extent or another from birth, as these situations arise natually, which they will in a playdates with children that age. Again, not saying to stand back and do nothing, but to take hold of the situation and turn it around for good. It may not be a big deal to you, non-trivial as you put it, but if you are open to think from another perspective (which is inevitably what will be offered to you on a message board) then consider if it would be a big deal if your child was the one being shunned for normal behavior. Consider if you think it would be more appropraite for the non-aggressor to learn how to play SAFELY with the aggressor while the aggressor learns to stop being aggressive. Yes, we all do have to decide what is the point we will walk away too, even as adults, so there is nothing wrong with that. At the same time, its good to teach tolerance. I hope you can find that balance, I know its hard to find. If we expect everyone to treat us perfectly (or even to just never treat us poorly) we would be lonely. We have all been hurt and we have all hurt others. Even in this own thread things you have said were hurtful to others, and you were hurt by things others said. Should we all leave this board and never return? Or never respond to eachothers posts? I think not. We can all afford to be a little tolerant. Toddlers exhibiting toddler behavior deserve some tolerance too. Yes, we can walk away if it becomes dangerous. We can also think a few foul plays will happen in the course of toddler play, and we can take measures to prevent them. What would hurt your child more, sticking around to play while her mom prevented her from hurt and helped everyone work through the problems? Or saying her playmates arent good enough for her? Only you know the answer to that. My personality leads me to be comfortable with less friends that are really valuable - perhaps you only want your child to be friends with children who are just like her in the sense they are never aggressive. Just consider the fact your child may be a late bloomer and become aggressive herself one day, and how she would feel if her playmates couldnt play with her anymore. A healthy tolerance never hurt anyone. Even I with my limited friends have high tolerance of the friends I do have. I pick onyl friends who treat me good, and I treat them good, but they have their quirks or they something say or do something that upsets me, but if I expected perfection I would be very lonely. I am sure there are things I do that they are tolerant of as well. When it comes to children the things that need to be tolerated aren't the same. It's more abou toy snatching and name calling and hitting. As adults its more about unintentionally hurtful comments, dissappointment, occasional let downs, possibly some broken promises, etc. Children are not as complicated as adults, and there is no need to complicate it this early on. Healthy Tolerance is a simple idea. Children are more forgiving then we are, and I think its not such a bad thing to let them be.
It's tough stuff, I hate seeing my children be hurt (hug to you)