London mayor, danish cartoons and my pistachios

So today, the London Mayor has been suspended over Nazi jibes to Jewish journalist.
How does one make sense of this when the whole journalistic world is aglow with utopic visions of free speech?
I read the cartoons-flamed-across-the-world, and frankly they were the silliest, most stereotypical images I have ever seen.
Everybody is of the opinion that in modern society Voltaire's attitude "detesting what you write, but giving up my life to make it possible for you to continue to write it" should be unanimously and globally adopted
But really, can something so intrinsically abstract be practically adopted?
And if it can, pray tell me why are there such disparate retributions in the world for comments, cartoons and caricatures.
I have a dislike to violent behaviour but aren't these violent protests also an extreme extension of free speech?
I will eat my pistachios and ruminate on this now.