Looking back at the historical documents at the time of World War II, we see that the concept of the nuclear weapon was itself likened to a tool of genocide. From the Minority Report of the General Advisory Committee to the US Atomic Energy Comission, dated October 30th, 1949:
Necessarily such a weapon goes far beyond any military objective and enters the range of very great natural catastrophes. By its very nature it cannot be confined to a military objective but becomes a weapon which in practical effect is almost one of genocide...The fact that no limits exist to the destructiveness of this weapon makes its very existence and the knowledge of its construction a danger to humanity as a whole. It is necessarily an evil thing considered in any light. For these reasons we believe it important for the President of the United States to tell the American public, and the world, that we think it wrong on fundamental ethical principles to initiate a program of development of such a weapon.
The letter makes a powerful moral case for stopping development of the "Super" and was signed by Enrico Fermi and Isidor Isaac Rabi.
Israel's stuation in today's world is certainly analogous to the position America found itself during WWII. In fact I believe that the very nature of these weapons guarantees that their invention requires a kind of urgency of purpose, linked to survival itself. Germany and Russia both pursued nuclear research but could not succeed - was this failure simply providence, or was it due to the nature of their intent?
WMG are much like nuclear weapons, in that their manufacture is closely intertwined with a host of technologies that hold great promise for teh human race. The question is can the technology be tamed. Rather than applying moral technology to evil ends, our nuclear know-how today grew out of weapons research, the other way around. So the question of "should these weapons be developed" is as much a matter of politics and social engineering as it is of simple technical expertise.
For example, in the context of WMG - consider the emerging field of pharmacogenomics, the science of genetically tailoring pharamceutical drugs to an individual's DNA, to reduce harmful or even lethal adverse reactions. It's obvious even to a layman that pharmacogenomic research has "dual-use" application to weapon design, which the British Medical Association has also noted:
Research into the development of specific treatments for many medical conditions (both genetic and acquired) using genetic knowledge and genetic techniques, is currently consuming a significant proportion of the pharmacological research budget internationally. This research considers essentially the same molecular techniques as would weapons development.
That there are ethical considerations in development of a Weapon of Mass Genocide is obvious - but in researching the issue, I've realized that my earlier view of the base morality of such a research program was too binary. I disagree with Fermi and Rabi, even as I admire them for their conviction (and feel the resonance of their appeal). That Rabi and Szilard and Einstein, all Jews, could be on opposite sides of that debate 60 years ago also seems to insulate any Jew today from pressure to condemn new technologies today.