"Then I'm not allowed to criticize your opinion?"
If you want to make a big song and dance about it, then do so. It won't change anything, nor in fact do anything. I'm not trying to convince anyone that I am right and everything else is wrong, I am simply considering a hypothetical situation, in the manner of one of Geoffrey Robertson's.
As to your next points, those issues were already raised. My state would not tolerate the existence of WMD in the hands of a neighbour or regional neighbour unless they were a firm ally. If they attempted to develop them under any other circumstances, then the development program will be destroyed by conventional means if possible (think Osirak), or failing that, a nuclear ultimatum.
I am not presenting a criteria of behaviour for the international system; I am putting forth a course of action for our own state. If another state attempted to do the same to us, or develop the ability to do so, then they would be prevented. I would not allow a level playing field, but would use any means necessary to defend the state, which is an underlying point of mine: If you have the means to defend yourself, you must at least countenance their use.
In answer to your question:
"And what if the country you attack with nuclear weapons has itself the bomb, or allies that have it, will they be allowed to use it against your state (according to your criteria) because you threaten their interests? What will you do to prevent that? Kill them all before they strike back?"
Yes. If it came to that, destroy their ability to strike at you; in a sense, kill them all. I am not advocating nuclear carpet bombing in every circumstance, no matter what, but neither am I letting there be any situation where I would not employ every means available to defend the state.
As I have previously said, do unto others what they would do unto you, but do it harder, more often and better.
The matter of "what if's" is another matter. Needless to say, a nuclear policy such as this would be accompanied by heavy employment of TMD, and BMD, as well as preemptive actions using massive force.
"You have made your point yourself, pardon me if I think it's the point of a madman."
Resorting to personal abuse because you disagree with a hypothetical point is not the mark of a polite individual. It is clear you disagree. Fine.
But to label someone mad on the strength of one thread is quite silly and immature. I am quite sure that I am not mad, thank you, and so is everyone I know. To abuse someone who disagrees with you is not the sign of a good case. Why is defending one's state with every means available mad?
You can certainly argue that the use of nuclear weapons can be in so cases construed as immoral, but it does not follow that it is insane.
Mutually assured destruction would not exist under the system I put forth in this hypothetical. Or rather it would, in the form of, "if you attack us or ours, then you assure YOUR destruction, and WE assure YOUR destruction as well"
