For all practical purposes, you are god. Manhattan has command over matter, is immortal, can create copies of himself, can change his size at will, can see the future, and so on.

Essentially his story is about a man in an alternate timeline during the Cold War, becoming a god on accident, who then slowly grows weary of human problems and bickering the more he loses touch with his own humanity.

He could fix mankind’s every problem, but what are their problems even on a cosmic scale, how petty are they in their fights over ideology and resources? And every time he does it they want more and more from him.