In case you haven't seen it yet, watch Barney Frank demonstrate how lunacy is properly dealt with. After being told Obama's policy proposals were the same as the Nazi's, complete with a picture of Obama with a Hitler mustache, he responded with:
On what planet do you spend most of your time? ...It is a tribute to the first amendment that this vile contemptible nonsense is so freely propagated. Madam, trying to have a conversation with you is like trying to have a conversation with a dining room table. I have no interest in doing so.
This is the proper response to intellectually dishonest wackiness. Chop them off at the knees. Deny them the respect they need and crave. Whether it is a LaRouchian, a cdesign proponentsist, Bill Donohue, or Glenn Beck, the answer is ridicule, not rational respectful argument. Otherwise, they stretch the Overton Window to their advantage.