How should the West respond to Putin’s threats?

Vladimir Putin clearly wants us to worry that he is crazy enough to use a tactical nuclear weapon in Ukraine. This fear was intensified this week when images surfaced that some – possibly in error – believed showed a train operated by the secretive nuclear security forces moving towards Ukraine. Despite this, many believe the likelihood of a nuclear attack remains extremely low. Yet it is a plausible enough threat for the West to be considering how it should respond if Putin were to unleash one.

Russia has an estimated 1,900 non-strategic nuclear weapons (NSNWs), from artillery shells to warheads for missiles; their yields range from a mere 0.5 to 100 kilotons, more than twice the power of the bomb that devastated Nagasaki. However, Russia has not tried firing one in an exercise since 1990, and we do not even know how many are still usable, even after an inevitable overhaul.

Putin has a range of options short of directly striking Ukraine, from overtly beginning to ready a warhead for use through to a performative ‘test’ on Russian soil or in Russian waters. However, if NSNWs are used, their purpose would not be so much to dominate the battlefield – Kyiv is unlikely to pack its forces conveniently tightly together to make this worthwhile – as to shatter Ukraine’s military or civil infrastructure and above all to try to terrorise them. The hope would be that Kyiv would back away or surrender, or that a horrified West would force it to come to the negotiating table.

It is unlikely that either scenario would happen, but the fear that Putin might believe this would work is what keeps strategic planners awake at night. The kind of measures which would either be demonstrated to try to deter this kind of scenario or else deployed in response fall into four main categories.