Willy Loman, from the play Death of a Salesman,
cannot face the reality that he has misdirected his energies and talents chasing a dream that never had any chance of materializing.
Therefore, any chance he had at success was stifled and buried when he forced himself to ignore his "true self" and raise up himself as something he was not (and could never be): his ideal self. He, himself, corrupted his own chances of achieving the (his) American dream by creating a self which had no chance of obtaining the dreams and goals he set.
An example of a closing which would conclude an essay on Willy's corrupted view of the American Dream (based upon his own lies and acceptance of appearance over reality) could look something like this:
In the end, Willy Loman, a man who held onto the fact that lies and appearance were more powerful than reality and truth, failed to realize that his disillusions ultimately decided his fate for him. It is only through one's ability to see the truth in life that one can fundamentally find their own American Dream, which is not obscured by lies and appearances. Perhaps if Willy would have accepted his life as it truly was, he could have found peace with the American Dream he had already succeeded at possessing.