In nonlogical sight, the disparity in technology development between nations which caused by globalized treaty such as NPT seems like undesirable. But I think this situation can occur as far as it goes, just for under the public interest such as if these global treaty could protect us from serious crisis like nuclear war.
For example, there are some countries which already have nuclear-weapon such as USA, Russia and so on. These countries impose sanctions against non nuclear-weapon countries' management or produciton of nuclear-weapon. In a way, we can think that all countries can develop and manufacture nuclear-weapon because all of us have right to develop their own technology. I think there is no logical problem just in this sight. But if they have any intention or issue to threat global peace, they have to be banned enough by the other state. In this sight, we can think the restriction can affect to one country's technology development for terrifying nuclear but I think that causing injury on public interest just for their individual beneficial is undesirable behavior. In my thought, disparity in technology developement between nations can be happened under specific condition which protects public interest.
We can say that these situation caused by the centralized social structure such as attention for global peace by non nuclear-weapon. For example, as global seeks for stable life, 'peace' became very important part to us. This concept made a common idea for the world that avoid experimenting or using dangerous weapons and caused the centralized social structure such as USA restricts administering or manufacturing nuclear-weapons of other countries. In my thought, some social concept which seeks for public interest makes a centralized social structure centrally powerful nations, groups and so on. If centralized social structure formed, the disparity of development in technology or something happens unescapable like fuctions which has cause and effect.