I don't want this post to be TOO long-winded, but let me at least try to outline this:
1* Speech, whether written or spoken, can be informative (AKA "constative") but may as well not - it can be "performative".
When a guy with a baseball bat say "I'm going to hurt you", that's not a constative sentence. That's not trolling. That's "threatening".
2* Let's define trolling as "person A expressing statements X he does not believe in, where statements X use highly evocative language, are designed meticulously to contain views which target audience disagrees with and will be angered by. X can be formally wrong and usually are as incoherent and ignorant as is possible without getting so contrived as not to be trusted as actual beliefs of person X."
3* Many people are ignorant in many different fields, while retaining an illusion of competence. We should know better than to lash out, get angry, insult them. If we (think we) know the truth - we should try to explain it.
4* If neither person X nor person Y know the truth, yet have mutually exclusive convictions on the subject, they should try to search for the truth together, perhaps asking a wise man, person Z, to tell them who (if anyone) was right.
5* If a matter is subjective and no objective truth exists, person X should listen to what person Y thinks, if only to understand him better and possibly enrich their minds and souls.
6* If a person is unreasonable - getting upset is helping no one. If you can't reason with someone - either wait for them or help them to change that. If that fails - walk away.
7* Con artists don't manage to scam people out of their money because their "mark" is too gullible and innocent. On the contrary - "you can't con an honest John". People get scammed because they want to exploit others and in turn - get exploited themselves. Kantian justice, you might say...
8* Trolls don't thrive because people are reasonable, nice and helpful. Quite the contrary - troll would be helpless in such a community. They'd get smothered will calm explanations, love and understanding.
9* To all of you people lamenting "psychological traumas" which can occur - the ancient stoics would disappointedly shake their heads at you and call you pussies (in their fancy ancient terms).
Being sensitive is great, I would know. Being weak, on the other hand, is pitiful.
Children growing up in sterile environments develop allergies. Trying to shield ourselves from criticism, different opinions and even - yes - mean and stupid people... will make us unable to exist in a diverse, complicated world. Our imagination will also grow barren, as well as our mind in general.
No, I'm not saying we should be gluttons for linguistic punishment. However - just as pointless, painful and regular struggle hardens the body and helps it develop, so do mental ordains with the mind.
10* A personal anecdote - trolls don't thrive among philosophers.
I had classes with one guy, who tried virtually EVERYTHING to strike a debate, or better yet - a heated discussion. We've had Hitler for a few months straight, firemen, marriages, death penalty, torturing people, church-state segregation... Pretty much NOTHING worked. While the guy was "innocently" providing us with will more and more controversial topics and statements, people just sat there, calmly gazing at him and waiting. We had a few discussions, but only because he cracked and started asking questions, which we tried to analyze like the little pros we were.
11* Trolling pretty much requires the person doing it to be more intelligent, socially competent and composed than his victims. Think about it - it's not about saying something, ANYTHING and wondering what will happen (that's what I love to do!). A troll "wins" when the trollee acts the way he planned, he predicted, he wanted him to. This might be my personal little pet peeve, but there is nothing, NOTHING more insulting than (apparently) reducing a person to a thing (objectifying), an algorithm you can analyze and predict, a puppet you can manipulate to do what you want it to.
12* A) If you can outsmart a troll - you can confidently and patiently dismantle his arguments, making them null and void. If he repeats them without proving your explanation wrong - you can recycle, though at this point you can either out such a person as unintelligent, unreasonable or proceed to B.
B) If your social intuitions are correctly attuned - you win. You figured out he was a troll, you're immune to all further attacks.
C) If you're a calm and composed (some might say "stoic") enough person - you win. Your mind cannot be breached, you will not throw a fit, the troll is wasting his time on you.
Remember - you only need to be superior in ONE category.
13* To conclude this little analysis - I think people should be smart, empathetic and composed. Trolls don't prey on good people - they attack the weak {side note: a "virtue" is "being good (at something)". Being "weak" is the opposite - it's a BAD thing. Don't let Christianity tell you otherwise. "Strength" means "virtue". For further reference - check out Nietzsche or simply contemplate which is better: pwning n00bs or getting pwned and being a n00b}.
14* Are the trolls to blame ? In some cases - perhaps. I'm not sure about all of them.
Are the trollees to blame ? Certainly.
Am I going to let someone "clever" make an analogy to blaming rape victims ? Most definitely not. What's the difference ? Here's the most amazing thing, which the ancients already knew - the only trauma a victim of trolling suffers is the one he brings upon himself. A moronic statement can't hurt you. A logical fallacy, in itself, can't do jack.
15* Be strong, be nice, be reasonable. Shove that red minus into the depths of the web, if need be. Mark spam as spam. If you get angry - don't blame anyone but yourself, or better yet - don't blame ANYONE. Just stop it and think. Thinking is what earns you the right to call yourself a human being after all...