Just a few comments. [1] Because of all-pervasive propaganda it's difficult to disentangle all the threads here. [2] These comments are just an overview.
Three test ban treaties are listed as
* August 5, 1963 'after more than eight years of difficult negotiations' USA, UK, USSR (USSR known generally as 'Russia') signed the Limited Nuclear Test Ban Treaty, which banned nuclear weapon tests in the atmosphere, in outer space and under water. This seems to leave underground tests, difficult or impossible to distinguish from earthquakes. From the 'nuke lies' viewpoint all this must have been to preserve power relations - note the period starts after the Korean War. For PR reasons, 'concerns over radiation' were quoted though this must certainly have been more or less invented.
* 1968 Nuclear Non-proliferation Treaty, 1968. Non-nuclear weapon states prohibited from, among other things, possessing, manufacturing or acquiring nuclear weapons or nuclear explosive devices. China and France must have been included in the fraud. India, Pakistan and Israel 'declined'. My guess is India and Pakistan were encouraged, so that Israel would not be the only exception.
* 1996 Comprehensive Nuclear-Test-Ban Treaty (CTBT) bans all nuclear explosions in all environments, for military or civilian purposes. Adopted by the UN General Assembly on 10 September 1996 'but it has not entered into force'.
From the point of view of nukes as fake, these treaties must have had several objects:
[1] Hoax maintenance - to preserve the myths. This includes continuing to support the full cost of 'nuclear weapons' systems and all the associated propaganda and fake news and fake research.
[2] Hoax maintenance includes clamping down on uncontrolled attempts at verification by duplicating experiments - hence test bans become necessary. Note that the reason given for test bans was fear of radiation (hence probably the fake Lucky Dragon Japanese fishing boat incident) - rather than fear of being wiped out!
[3] Hoax maintenance includes a personal element - politicians and scientists prefer not to be exposed, at least while alive.
[4] Demonstrating that a nuclear bomb works becomes impossible - this is against the terms of the Treaty!
[5] Political maintenance - to continue the use of the threat of nuclear weapons to maintain or increase power, or at least not let it decline very much. Obviously if the things are fake, genuine military power will be reduced by the money spent on fraudulent projects. But once a fraud passes a certain point decisions become difficult.