David P. Barash, professor of psychology at the University of Washington, in a symposium in the Chronicle of Higher Education, September 28, 2001:

The "need" for retaliation is bruited about, such that it seems beyond question, although an evolutionary and "human nature" perspective would ask why such a need exists, and whether it is truly justified, or likely to be counterproductive. If it is human nature to seek revenge, then it seems that an equally human nature motivated the perpetrators, who perceive themselves to be seeking revenge. If the United States, in its righteous anger, will "make no distinction between terrorists and those who harbor them"—in the words of President Bush—then, in view of the fact that many people consider the United States to be a terrorist state, weren't the perpetrators following just such a policy in attacking innocent civilians—making no distinction between their view of the terrorists (our government, our country) and those who harbor them (ourselves)?

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