I can see why a nation would want to defend itself - or have the capabiltiy or deterrent of a nuclear weapon to do so.
Obviously it's quite worrying that a potential enemy may have WMDs aimed at a country you live in - though there probably reasons as to why they are aiming at one country and not another.
At what point does another country decide that you can or cannot have nuclear weapons? Is it because you are their military allies which has provided personnel or bases to use in the past? Or have strong business and commercial links etc?
What if another country is so worried that another may be developing WMDs that they discredit that country with false and exaggerated information as a prelude to invasion and then install their values upon that nation?
Or that false infromation if given about WMDs in that country as a reason to interfere - what would happen after? - an apology with immediate withdrawl? Being shunned by the international community' or an emargo against the perpetrators?
^ what would you judge to be fair and reasonable?