Monday Morning Morals Questions - Am I a bad person if...???

Hello again - and I hope you all are doing something special and remembering our fallen heroes on this Memorial Day.
I've been on a week-long hiatus.  I wish I could say that I was doing something fabulous like scaling the Great Wall


or looking for aliens at Machu Picchu with Shirley Maclaine.
 

But instead I was just here, helping Alex get through what has become known as The Worst Last Week of School EVER!


This post will give you a snapshot of what I'm talking about.

Last Sunday, Zach had a "promotion celebration" for the Cub Scouts.  He was moving up the ranks from Wolf Scout to Bear Scout.  We were very proud...that's a different story.  Anyway, the event was a big family picnic with all the siblings and whatnot.  We all had a good time...or so I thought.
At one point, Alex was climbing a tree and wanted me to watch.  I watched and clapped and said all the mom-stuff ("that's so great honey" blah blah blah).  Anyway, he came over to me to talk for a few minutes, and in the meanwhile 3 kids who are notorious bullies from his school climbed the tree.
After a minute or two Alex decided he wanted to climb up again, and as he did, the three bullies started throwing wood chips and pine cones and other non-deadly yet still annoying objects at him, telling him to get down.
Alex, to his credit, was annoyed but not dissuaded, and told the kids it wasn't their tree and he could climb it if he wanted. (Yeah Alex, I'm so proud of you for standing your ground!)
But then, the youngest of the three said "Here comes Hitler!  Go to hell, Hitler!"  The other 2 joined in calling him Hitler and telling him that he deserved to go to hell.  Within a minute or two he'd had enough and climbed back down.  He came over to me, and told me that the tree was "too crowded."  I had noticed the bullies so I rolled my eyes in understanding that they were the reason, but didn't ask any more questions at that time.
Fast forward an hour or so and Alex is now holding back tears trying to pretend that he's fine.  Of course, momstinct kicked in, so I pressed him for what was wrong and he eventually told me about the Hitler comments and the "you deserve to go to hell."
Well, I had had it with these kids.  Throughout the school year they had been harassing and teasing Alex, and throughout the year I told him that they were idiots, it was them not him, and not to listen to them.  But this time, I got really mad.  I composed a snippy but to the point message...well, here - I'll just show you what I said:
Dear [names omitted to protect the guilty]:
This afternoon at the Cub Scout meeting your kids [once again, names omitted to protect the guilty]were harassing Alex, and ultimately told him that he is "Hitler and should go to hell."
I know that 10 year old boys can be stupid and rude and I suppose I should chalk their behavior up to ignorance and bad manners.  Generally, I ignore these kinds of comments and tell Alex to do the same, but seriously, this has gone too far.  This type of verbal abuse at the tongues of your children has plagued him this entire year, and I will tell you that I will no longer tolerate this rude, antisocial and cruel behavior. I suggest that you tell your boys to absolutely NEVER talk to my son (or ANYONE for that matter) like that again. Frankly, I'd be just as happy if they were to never even speak to him again at all.  But I can assure you, if you do not take care of this in your own homes and this type of harassment continues, I will be forced to take further measures.
I know for certain that this is not the first time that you are being made aware of your sons' bullying or inappropriate behavior.  Obviously you have not taken it seriously in the past.  I suggest that you do not make that same mistake again, at least with respect to their behavior toward my children, as I have no intention of just letting this slide by unnoticed.
Sincerely,
Lorraine
And within minutes, this is the (VERBATIM and unedited) response that I received from the father of one of the bullies:
Dear lorraine, lighten up, will ya? If u can't lighten up and take a mature attitude towards these types of problems yourself, then I suggest u stick it in your ear. Sincerely,
I'd like to say that I left his name off intentionally, but it was just signed "Sincerely," without more.  I have an immediate problem with anyone who writes "u" instead of "you," but that was overshadowed almost instantaneously by the "mature attitude" of the "stick it in your ear."
Anyway, I think it goes without saying that i was really pissed at this point, and I admit that my actions were in large part guided by anger, but my next move really brought in the big guns.  I forwarded the entire email chain to Alex and Bully #1's teacher, as well as the principal of the school accompanied by this note:
Dear [Teacher] and [Principal],
Below please find correspondence related to an incident that occurred outside of school between Alex and [Bully #1].  Of course I don't expect any kind of intervention for this particular incident, but I wanted you to be aware that the bullying problem at [school] is very real, and obviously is not sufficiently dealt with in the homes of the bullies themselves, so probably needs to be addressed more seriously in the classroom.
Sincerely,
[me]

So my question is this, am I a bad person for forwarding that along to the school?  Please consider the fact that the only reason that I did so was because I was angry at the obnoxious response I received from the dad of Bully #1.  Does this affect your answer in any way?
And a secondary moral quandary...the parents of Bullies 2&3 (brothers) are firm believers in this "let kids resolve their own disputes" kind of parenting.  They don't believe in imposing punishment of any sort because the "natural consequences of their actions" will teach them how to behave. They don't "make" their kids apologize for things because they feel that when the kids realize the effect of their actions, an apology will necessarily follow in an attempt to make reparations.

So, am I a bad person for deeming them the laziest, most naive parents ever, too?

PLEASE, JUDGE ME!