You don't generally need either miniaturization, nor a nuclear triad, nor MAD. Those are only a requirement if you are defending yourself against an adversary w

You don't generally need either miniaturization, nor a nuclear triad, nor MAD. Those are only a requirement if you are defending yourself against an adversary with a ton of nuclear weapons of their own and significant nuclear countermeasures. If that is the case, then yes, it is going to take a massive investment to build and maintain that capability, which is the reason why most developed countries don't bother. But if you only want tactical nukes, it doesn't take that much. I could not care less if e.g. Italy, Spain or Finland have developed nukes in secret. It would not surprise me one bit, either.