TheGreatBarryB
Hall of Famer
Haven't seen it yet, but intend to, especially after the comments above.
My view from reading the comments, reviews and trailers is that this character might be the tragic story that serves as inspiration for the "real joker" who this character meets in Arkham.
In my mind Joker is only insane in the sense of his commitment to the cause - a brilliant mind, military strategist, a charismatic leader of men, perhaps even a man of the highest ethical and moral standing - working for the military at elite level who ultimately lost faith in the 'traditional' structure of the world, perhaps triggered by a truly heinous crime against humanity (slaughter of innocent women and children for example) instigated and then covered up by his bosses/PR for the benefit of $$$ and snaps - unable to reconcile his experience with the world outside, he is sent to Arkham as a rambling lunatic. Upon meeting this character, and discovering the opinion of society has changed, he embraces the opportunity for all that chaos provides.
Joker should be the equal to Batman in all things other than physical size/power and his code of ethics. Batman still believes in the "system", Joker knows the truth.
Exactly, far more interesting if we had opportunities in life and you wonder why? Even Colonel Kurtz-like.