That isn't the case in NZ; Most of the population trusts the government and value's collective good above individual liberty, the policies and responses to events like these are born out of our culture and focus on those values. It's apples & oranges with the US culture of valuing individual liberty.
I do feel that to say that it's solely personal responsibility is to disregard easily mislead demographics (specifically the youth). Of course the plan is to educate them so that they can reason these situations out for themselves, but until then it's societies duty to look out for them, and to ensure they're not being exposed to unnecessarily harmful views.
Personally, I believe some people can't actually be reasoned with all that well; You can try, but eventually you exhaust yourself without ever changing there mind; What's the saying about "the world changes when old men die"?
As a final counter-point. My understanding is that Osama Bin Laden never personally attacked the US. It was his hate speech that incited violence, it was his ideology that was his weapon. The response to that was to condemn a man who was not US citizen to death without ever having a trial. I'm not saying he shouldn't have been killed; I'm asking why one incitement of violence, of hate speech; is acceptable and should be allowed when another is not? (keeping in mind that both are in relation to a terrorist attack).