Russian President Vladimir Putin is fond of nuclear saber-rattling: On the eve of Russia’s full-scale invasion of Ukraine in February 2022, the Kremlin leader presided over the rehearsal of a nuclear strike,

Kremlin spokesman Dmitri Peskov said on Sunday that Moscow's revised nuclear weapons doctrine is needed because NATO infrastructure is approaching Russia's borders ever more closely. Peskov told Russian state television that Western powers are seeking victory over Russia through their arms deliveries to Ukraine.

Putin has extended the list of scenarios that could lead to Russia using nuclear weapons. Whether he means it is a question critical to the course of the war. If he is serious, the conflict could turn into World War Three.