Hillary Clinton accepted the criticism of her reference to the possibility of an assassination changing the landscape of the nomination process, and apologized. The question isn’t whether it was wrong to suggest such a catastrophe, especially when many fear that Barack Obama, as a black man, is at greater risk of violence than a white candidate. It was. The question is why this didn’t occur to Senator Clinton before she made the remark.

We can’t be sure that it didn’t, of course. Those who believe, with not insignificant justification, that there are no ethical boundaries that the Clintons won’t cross in their pursuit of power will draw other conclusions. The darkest view of Hillary’s ruthlessness, holds that she calculated that “inadvertently” injecting this fear into the minds of voters and Democratic leaders was worth the short-term criticism she would take as a result. That possibility doesn’t need to be discussed here: someone with the most shriveled conscience could recognize this as the unethical tactic it is.

But assuming that the implication was not intended by Clinton, the gaffe still gives us insight into her ethical make-up. It appears to be an example of “signature significance,” the concept first described by baseball analyst/philosopher Bill James: a one-time act that defines the actor, and cannot be argued away as just a random occurrence. For example, when comedian Michael Richards went on a racist rant on stage, his later excuse that it was a one-time aberration didn’t wash. People who aren’t racists don’t have racist rants in public, not even once.

Ethical conduct is often governed by how early the ethics alarms go off and how loudly. Almost none of us are thinking about ethics as we go about the daily chores of life, love, and survival, but most of us have triggers that shift our thoughts to considerations of right and wrong. Those triggers—the pain of others, basic societal taboos and norms, lessons taught by parents and authority figures, direct references to moral imperatives—focus our attention on ethics and promote ethical analysis.

Sociopaths lack these ethical triggers. And some triggers become jammed, rusty or useless from misuse or neglect, as with the politician who tells lies without guilt, the lawyer who aids and abets unscrupulous clients, or the student who routinely uses the work of others in his term papers. Rationalizations, those lies we tell ourselves to make being unethical seem acceptable, are essentially ethics trigger-locks.

Destroying political enemies with scorched earth tactics has long been the Clintons’ calling card, and it has been a successful strategy. But just as soldiers who are trained to hate the enemy in war become more likely to commit atrocities (the ethical triggers against causing pain and suffering to others have been disabled), so politicians focusing all emotion, passion and energy on defeating a political enemy be unable to sense when bold ethical lines are about to be crossed.

This is what happened to Senator Clinton. Nobody whose ethical alarms are in working order would ever make a public statement evoking the mid-campaign assassination of Bobby Kennedy as a justification for not rushing to award the Democratic nomination to a black man, especially within days of the news that Senator Ted Kennedy has an inoperable brain tumor. Long before such an idea traveled from brain to mouth, a person with a functioning ethical alarm system would be hearing a deafening din: “You can’t say that! It’s offensive! It’s dangerous! It’s unfair! Fear mongering! Irresponsible! Mean! Insensitive!”

But for Hillary—silence. Her ethics alarms don’t work, at least right now. Whether they ever worked, and how well, is an argument for another day.

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