That does seem to be somewhat weird, although I do understand some of the sentiments behind it. However, I must admit that I find the idea of spraying Prozac and/or Zoloft into a massive crowd fairly amusing... maybe as a "time-elapse" sort of thing. Not terribly effective, though.
It's not so simple. Do you want Bush to come back by saying, "Listen John Kerry, you peacenick Bitch, we are gonna ass rape you in '04!"? Politicians are supposed to be civilized. They can't deteriorate to that level of mudslinging.