The new nuclear arms race?

[Blast]

Many countries, such as the Ukraine, agreed to stop developing nuclear weapons because the US said they'd defend them, instead. These agreements were made to stop nuclear proliferation. In light of current events, how many of those countries will now be restarting their nuclear weapons programs?

And FYI, after the fall of the Soviet Union, the Ukraine was likely the 3rd biggest nuclear power in the world until they agreed to turn everything in. But did they? 
-Blast

[aikorob]

SIL and her husband are both physicists --university professors.
Story in family is that "some people" talked to them about this subject after Crimea invasion