Just my observation:
Over the past 6 months George Bush has been maintaining a conscious effort to avoid the word 'Nuclear', since he is unable to pronounce it and has taken so many 'zingers' for it.
The usage of the synonym, 'Weapons of mass destruction' has apparently been mandated for all to use. You rarely hear that 'n' word from the mouths of any administration official these days.
Last night, when Kerry replied that 'Nuclear Proliferation' was our greatest threat, Bush offered that yes, it was 'Weapons of mass destruction', (not 'Nucular' material) which was the greatest threat.
Just thought it amusing (-:
Jim Lehrer did a fantastic job of organizing & leading this debate - the best one I have ever seen & I go back to Kennedy/Nixon times.