But history shows the denuclearization to have been a chaotic upheaval that shook with infighting, reversals and discord among the country’s government and military. At the time, both Ukrainian and American experts questioned the wisdom of atomic disarmament. The deadly weapons, some argued, were the only reliable means of deterring Russian aggression.

Today Ukraine has no easy path to producing or acquiring the materials to build a bomb. Even so, the nuclear genie is once again stirring as Russian troops encircle the nation and wage a shadow war in its easternmost provinces.

“We gave away the capability for nothing,” said Andriy Zahorodniuk, a former defense minister of Ukraine. Referring to the security assurances Ukraine won in exchange for its nuclear arms, he added: “Now, every time somebody offers us to sign a strip of paper, the response is, ‘Thank you very much. We already had one of those some time ago.’”