The funny thing about technology is that we define it as applied science. That is we learn a scientific principle and apply it to create technology. What is funny about this is that this paradigm is quite young. It is no more than a century or so old, and I suspect that it was not the dominant paradigm until the creation of the atom bomb. Previously we created technology first and then gradually figured out how it worked through science, often long after the technology had been developed. Do you think the inventors of gunpowder understood electron valence and such? This is relevant to cold fusion because the observed phenomenon is not explainable with our current knowledge of physics, chemistry, or electronics. When it was first presented the vast majority of attempts to replicate it failed. Today the situation is reversed. "Cold fusion" experiments are readily replicatable. That is, the heat measured leaving the cells is greater than the electrical energy measured entering the cells. The physical setups appear to be critical, and subtle factors such as the quality of the palladium used have a large impact, which is why measurements of excess heat are more repeatable now.

 

The question is, where the excess heat comes from. The obvious initial explainations ware measurement error on one hand and cold fusion on the other. Measurement methods have become much better, but so far the experimental methods have not been able to rule out chemical sources of the energy, because our understanding of the electrical and chemical effects that are occurring in the cells is not complete.

 

As to weapon applications, cold fusion is not a weapon technology per se, but could potentially be used to generate electricity. Also if the cells are able to be made to work, there is thought to be no intrinsic lower limit on the size of a cell.

   It's sad but true but human beings have always sought to use what little technology we have and turn it into a weapon. Eventually we may create efficient cold fusion and it will be installed in war machines off all types.