My knowledge of the holders of nuclear weapons is limited. The 5 admitted members, UK, France, US, Russia and China. An acknowledged suspect is Israel, who do not admit it but also do not deny it. Other EU countries house nuclear weapons and as such should be included in the list of "holders".
All the above "may have concealed nuclear programmes" and undeniably sponsor "terrorism".
Iran is "suspected" of a nuclear weapons programme, but not proven, and is "suspected" of having sponsored terrorism, but not proven.
When the acknowledged holders are subject to the same level of required proof, then you may have a point. Until then it's just bullying, which is against the UN charter.