THIS column wishes respectfully to propose a temporary ban on references in political debate to both American greatness and American exceptionalism. This is not because Lexington denies that America is great and exceptional. It is. The case for the ban is that both terms have been emptied of serious meaning, converted into slogans and pressed into service, especially by the right, as a club with which to bludgeon political opponents. They should be put aside at least until America emerges from its present economic crisis, and perhaps for longer.