After the fall of the Soviet Union, there were suddenly many new countries that had nuclear arsenals. Growing concerns over “loose nukes,” terrorism, and regional instability meant that negotiations had to happen.

The result was the Lisbon Protocol, or the agreement that the nukes in Ukraine, Belarus, and Kazakhstan would either be sent back to Russia or destroyed. At the link, you can read about three U.S. FSOs who helped out with the negotiations and inspections needed to make the protocol happen.