Why Ukraine gave up its nuclear weapons -- and what that means now.
https://www.npr.org/2022/02/21/1082124528/ukraine-russia-putin-invasion
Three decades ago, the newly independent country of Ukraine was briefly the third-largest nuclear power in the world.
Thousands of nuclear arms had been left on Ukrainian soil by Moscow after the collapse of the Soviet Union in 1991. But in the years that followed, Ukraine made the decision to completely denuclearize.
In exchange, the U.S., the U.K. and Russia would guarantee Ukraine's security in a 1994 agreement known as the Budapest Memorandum.
SNIP
But they were told at the time that the United States and Western powers so certainly at least the United States and Great Britain take their political commitments really seriously. This is a document signed at the highest level by the heads of state. So the implication was Ukraine would not be left to stand alone and face a threat should it come under one.
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