First, it assumes that the reason non-nuclear weaponstates wish to obtain thermonuclear capabilities is to emulate the U.S. and others who possess such weaponry.
The NPT offered non-nuclear weaponstates all the know-how and most of the materials they needed to become nuclear armed, if only they promised not to do so.
And we recognized the value of national negative security assurances -- assurances that the United States and other nuclear powers have made that we will not threaten -- use or threaten to use nuclear weapons against other state -- non-nuclear weaponstates who are in full compliance with their NPT, nuclear non-proliferation obligations.
Notably, at the Non-Proliferation Treaty (NPT) review conference in New York where this statement was unveiled, some among the roughly 500 participating non- governmental organizations (NGOs) declared their intention to ask the World Court to order the nuclear weaponstates to set a timetable for complete nuclear disarmament.
In particular, proponents of a CTB routinely cite the prospect that developing nations will refuse to extend the Non-Proliferation Treaty (NPT) when it comes up for review in 1995 unless the United States and other nuclear weaponstates have agreed to suspend testing permanently.