Yes, Putin might use nuclear weapons. We need to plan for scenarios where he does | Christopher S Chivvis

Putin's saber-rattling doesn't necessarily mean he'll deploy nukes. But he certainly could

News of the Ukrainian army's recent advances swept across western capitals like fresh air. A war that was for months mired in crushing artillery fire had suddenly opened up. Russian forces, outmaneuvered by the Ukrainian army, fled, again proving weaker than anyone expected. Hopes lifted that Ukraine could win the war and force their tormentor back to the prewar battlelines - and perhaps further.

Russia shared the same assessment. Vladimir Putin knows his military is badly damaged and getting weaker. The Russian president responded with military mobilization and preparations to annex the Ukrainian regions Russia now controls, just as he did in Crimea in 2014. He also threatened to use nuclear weapons to protect Russia" - implying he may use them to defend the regions he is annexing.

Christopher S Chivvis is a senior fellow and director of the Carnegie Endowment's American statecraft program