Tense situations that prompt nuclear threats occur when one (or more) of three conditions exist: when the state issuing threats feels weak in some important respects, when other means of suasion are unsuccessful, and when the stakes involved are exceptionally high. Examples abound. Kim Jong-un threatens nuclear devastation when U.S. and South Korean troops carry out joint exercises. The United States resorted to not-so-veiled nuclear threats against China when bogged down in the Korean War. Nikita Khrushchev used veiled threats during the Berlin crisis. (“It is best for those who are thinking of war not to imagine that distances will save them.”) Pakistan employed nuclear threats when both armies mobilized after the 2001 attack on the Indian Parliament by extremists based in Pakistan. New Delhi threatened massive retaliation if Rawalpindi resorted to first use.
To threaten mushroom clouds when the stakes are low (see Kim Jong-un, above) devalues the currency. Ditto for repeated threats of mushroom clouds. Multiple nuclear threats are once again emanating from the Kremlin. NATO’s advance eastward and Vladimir Putin’s actions to reassert Russia’s sphere of influence along its periphery are the proximate causes.