Discuss the nature of a hero base on Watchmen. Heroism in watchmen?

A personal view: What makes "Watchmen" special is precisely that it moved away from the stereotyping of traditional comic characters as either good or bad, to portray them as something more akin to rounded personalities operating in the real world, where black and white merge into multiple shades of grey, a common Alan Moore motif. It is thus not about how people should or shouldn't behave, but how the stock characters of comic fiction might behave if they were something more than archetypal two dimensional figures. Hence the deliberate moral ambiguity. If you type 'Alan Moore interview' into the search box of Youtube, you will find a good deal of discussion to this effect, including talks given by the writer himself. However, you could argue that Adrian is THE villain because, whether or not his end is justified by his means, his megalomania sets in motion the chain of events which the rest strive to bring to a satisfactory conclusion. You appear to have been thinking on similar lines yourself.