Worse, an instinct for self-protection would almost certainly awaken in the other candidates a sense of caution, and therefore of sympathy for the candidate who didn't answer the question -- gradually chastening the moderator, who would get back to the kinds of general questions that leave the voting public with no opportunity to reflect on the weaknesses of the various candidates, let alone with any sense of who, on Jan. 3, is going to prevail in Iowa.
The election contest we are let in for has a great deal to do with how much money the candidates have succeeded in attracting from donors, fleeting impressions of how skillful they are in circumlocution, plus a certain fuzz of likability, or lack of it. This is not unimportant. If we are going to see the face of this man, or woman, 18 times a day for the next four years, why not choose someone with an agreeable countenance? And we are rewarded in having a glimpse of his capacity to deal with other politicians.
But Robert Strauss was right. You will never force a politician to recite the weaknesses of another. And this even though we know from history -- as witness, most recently, Arthur Schlesinger's posthumously published journals -- that this is often what most needed to be said.