I never said they're identical. I said that their offensive and defensive value is a based on their use. I will concede that nuclear, biological, and chemical weapons have other considerations that can make them potentially harmful outside of their use. For example, negligence in the construction of a nuclear weapon could lead to radiation exposure. Negligence in storing chemical and biological weapons could lead to exposure and harm to unintended people.
However, assuming no negligence on the part of the construction and storage of these weapons, they are inert and not a threat to anyone until they are used in an offensive capacity. We're talking about the NAP, correct? What is aggressive about a weapon that is never used to commit aggression?
I'm not suggesting you can't voluntarily dissociate with people who choose to own and utilize weapons aside from beanbags and pepper spray and tasers and what-have-you. However, your logic is flawed. Every weapon we've discussed is the same in this regard: they are neither offensive nor defensive until they're used for a specific purpose. You can't impute a purpose into a tool; the purpose lies exclusively in the person using it.
You're correct in asserting that they all have different capacities to cause harm. That speaks nothing to whether they are "killing machines" rather than "purely defensive" tools.
Well, there are some who would disagree as a matter of philosophy:
Whether or not we can come to an agreement on that point, we could step back and look at raw statistics from a purely cause and effect, materialistic determinism perspective. If weapons of mass destruction were openly available to anyone of the human species, would the amount of mass murder increase or decrease? If we argue it would increase because more people would have the ability to use them in immoral ways, then we have to go further and say, "Are we okay with that or should we do something about it?"
If we're okay with it because the logic is sound and only the individuals choosing to use them for immoral action have anything to do with the situation, then I'd say we're being logically consistent on one front while being completely illogical on the more important front of whether or not whole cities are being destroyed. It's like missing the forrest for the trees.
So, if we decide it's all about human action to actually use a device to harm someone else and that's all that matters but we have statistical data we could refer to that might tell us restricting access to certain things actually increasing well-being for the most number of people, what then? We could start discussing the best ways to restrict that access. I'm not convinced it would only have to be done via threats of violent government force. It could also be about education, social shaming, ostracism, etc.
We're talking in extremes here with weapons of mass destruction because I'm trying to find a point of common ground where we recognize the goal should be increasing well-being, not sticking to our dogmatic perspectives on what is logical and what is not. If someone nukes a city because they could easily get a nuke, the logic doesn't really matter much anymore, IMO. The facts of reality would clearly show we, as a society, probably should have done more to prevent easy access to something which is designed to be so destructive.
But, anyway, I've taken this as far as I can and since we're already buried deep in this thread, it's doubtful anyone else will benefit from this conversation. I appreciate that you have consistent logical perspectives to support your views. I hope you recognize that I too hold to those views while also working to understand statistically reality when it comes to what increases well-being and what doesn't.