Men make history, and not the other way around. In periods where there is no leadership, society stands still. Progress occurs when courageous, skillful leaders seize the opportunity to change things for the better.
No one who has not had the responsibility can really understand what it is like to be President, not even his closest aides or members of his immediate family. There is no end to the chain of responsibility that binds him, and he is never allowed to forget that he is President.