SF Bay Area
i am a physicist and therefore belong to a community that has a unique perspective of what can happen when science goes nuts, in fact we are acutely aware of how wrong it can go. fermi, bohr, einstein, oppie, and many others who were as far above us as we are above ants lived to see the horrible applications of their work in japan, chernobyl, and many other lesser known incidents. not to mention the lasting effects of the possesion of such technology and the resulting paranoia.
stem cells can lead to amazing new treatments for many debilitating conditions. conditions that 100 years ago would have meant death in childhood or earlier or simply death within months of the manifestation of symptoms. not to mention possible applications to many other conditions.
but we need to be obsessive about regulation and oversight. physics led to the atom bomb, chemistry and older biology have led to nerve agents and biological weapons that while not getting much publicity are FAR more scary than even nuclear weapons (think stephen king's the stand - we have that type of weapon and are developing more).
i don't know about any esoteric arguments based on difficult to justify ethics, or faith, or other arbitrary belief systems. all I know is that this stuff is dangerous and scary.
Timid thoughts be not afraid. I am a Poet.