Nuclear weapons are not only dangerous, but also very expensive to build and maintain, usually to the detriment of government services that would have benefitted tax payers of that nuclear state.
Since we are already have nine nuclear states, it is crucial that we look at the existence and control practically.
Of the 9 states, the 5 declared nuclear states (NWS) are seemingly responsible, with organized nuclear doctrines and political stability which somehow assure the rest of us earthlings that there wouldn't be a nuclear war when mutual respect is maintained between these countries.
The 4 remaining nuclear armed states i.e. DPRK, Israel, Pakistan and India are where our biggest nightnare could come from, not mentioning a possible new kid on the block, Iran - who are trying to enrich uranium to weapons grade.
These countries have proven rather irresponsible in their conduct, suggesting the use of nuclear weapons at any aggression, except of course Israel who have never accepted or denied having them.
I believe it was a huge mistake to allow these countries to have these weapons considering the leadership of these countries tend to act like kids at times.
To put this into perspective, imagine the chaos in a kindergarten. What if there was no teacher there?
We'd be looking at children assaulting each other over toys, for instance, instead of sharing them.
Now imagine giving AR15's to such children? Instead of assaulting each other, we'll be looking at death every time a child picks a toy being claimed by another child.
Due to the seemingly responsible nature of the declared NWS who are signatories to the Nuclear Non Proliferation Treaty (NPT), based upon three main things; preventing non nuclear states from acquiring nuclear weapons, ensuring nuclear disarmament and cooperation on peaceful uses of nuclear energy.
The NWS (the responsible 5) have failed in this, considering some of their hard headed allies have nukes already. They have also failed to uphold disarmament and keep talking about modernizing instead of relinquishing stockpiles and repurposing the nuclear material.
I find it prudent, for humanity's sake, that the responsible five objectively ensure they stick to the pillars of the NPT.