The best book, like the best speech, will do it all - make us laugh, think, cry and cheer - preferably in that order.
Often, these downplay the power of cultural imperialism - in that sense, playing the game of US interests - by reassuring us that the global success of American mass culture is not as bad as all that.
I don't know any form of art or entertainment that can affect people the way movies can. I know it sounds ridiculous, but they can change your world. They can change your views.