Excellent thread, Warlock.
I would agree that both theists and atheists can have the tendency to try to convert others to their way of thinking. Nvr summed up quite nicely as to why this is so. The question really should probably be, why do so many atheists here tend to be prone to do this? Here are a few possible reasons:
1. Ex-jws already have been taught through years of training to look at religion critically. Since many things concerning religion can be proven false through history or science, an ex-jw picks up on these rather easily through research, and these things learned become the basis for all belief thereafter.
2. Ex-jws have also been trained that what people believe is a life and death matter. An ex-jw is still prone to this black and white train of thought.
3. Faith and spirituality in general are things that are barely understood in the jw religion. Faith is completely associated with the FDS's explanation with absolute certainty of outcome. No contradictions are allowed or possible.
Atheism makes sense on the surface. Even better than how many once thought the jw religion made sense on the surface.
It is possible to look at belief in a higer power from a far more liberal viewpoint than many ex-jws do.
j