In the world of nuclear weapons, tactical means an exceedingly large amount of explosive energy and strategic means even larger. Most nuclear weapons today are variable-yield, or “dial-a-yield,” providing a set amount of explosive energy that can range from fractions of a kiloton to multiples of a megaton. (For example, the U.S.’s newest version of its B61 nuclear bomb can release 0.3, 1.5, 10 or 50 kilotons of explosive energy. In comparison, the Hiroshima bomb was about 15 kilotons.) Russia has about
4,500 nuclear warheads in its arsenal. Of these, the ones of largest yield—the “strategic” weapons—are deployed on submarines, bombers and intercontinental ballistic missiles.
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No one should imagine, however, that it makes sense to use a tactical nuclear weapon. A thermonuclear explosion of any size possesses overwhelming destructive power. Even a “small-yield” nuclear weapon (0.3 kilotons) would produce damage far beyond that of a conventional explosive. (For a graphic depiction, the interactive site
NUKEMAP, created by nuclear historian
Alexander Wellerstein, allows you to simulate the effects of a nuclear explosion of any size anywhere on the planet.) It would also cause all the horrors of Hiroshima, albeit on a smaller scale. A tactical nuclear weapon would produce a fireball, shock waves, and deadly radiation that would cause long-term health damage in survivors. Radioactive fallout would contaminate air, soil, water and the food supply (Ukrainians are already familiar with this kind of outcome because of the disastrous meltdown of the Chernobyl nuclear reactor in 1986).
No one knows if using a tactical nuclear weapon would trigger full-scale nuclear war. Nevertheless, the risk of escalation is very real. Those on the receiving end of a nuclear strike are not likely to ask whether it was tactical or strategic. In testimony before the House Armed Services Committee on February 6, 2018, then–Secretary of Defense James Mattis
stated “I do not think there is any such thing as a tactical nuclear weapon. Any nuclear weapon used any time is a strategic game changer.” Russian leaders have made clear that they would view any nuclear attack as the start of an all-out nuclear war.