There are a number of ways in which such a tactical nuclear weapon may very well be used to fireplace the form of “warning shot” envisioned in Russian navy doctrine. These choices include rising levels of threat for the U.S., Ukraine and its allies, and for Russia.

Listed below are three situations.

State of affairs 1: Distant atmospheric take a look at

Least provocative could be Putin’s resumption of above-ground nuclear testing — by detonating a low-yield nuclear warhead excessive above Novaya Zemlya, the previous Soviet take a look at website within the Arctic, for instance. Whereas each the precise injury on the bottom and radioactive fallout could be negligible, the psychological impact may very well be huge: It could be the primary nuclear explosion by a superpower since nuclear testing resulted in 1992, and the primary bomb detonated within the environment by both the U.S. or Russia after such checks had been outlawed by treaty in 1963. It could even be a potent reminder that Putin has tactical nuclear weapons in abundance — about 2,000 by final depend — and is ready to make use of them.

State of affairs 2: Atmospheric detonation above Ukraine

A extra provocative demonstration could be an ultra-high-altitude explosion of a extra highly effective weapon over Ukraine itself. In a 1962 take a look at, the U.S. detonated a 1.4-megaton H-bomb within the mid-Pacific, 250 miles above the Earth. The ensuing electromagnetic pulse unexpectedly knocked out streetlights and disrupted phone service in Hawaii, 900 miles distant. A equally highly effective explosion above Kyiv wouldn’t solely be visually spectacular however would doubtless plunge the capital into extended darkness and silence by shorting out computer systems, cellphones and different electronics. EMP results may additionally prolong into NATO member international locations. However the extent of injury from the heart beat is unpredictable, and Russian communications is also affected.

State of affairs 3: Floor explosion in Ukraine

Most harmful — and, for that purpose, maybe least doubtless — could be utilizing a tactical nuclear weapon to attain a concrete navy goal equivalent to disrupting the supply of weapons to Ukrainians preventing in a metropolis like Mariupol. Alternatively, Putin would possibly detonate a tactical nuclear warhead towards navy or logistics targets in sparsely populated western Ukraine — within the agricultural lands between Lviv and Kyiv, as an example — after warning folks within the goal space to evacuate. However even the smallest nuclear weapon would set fires over a large space if detonated within the air. Relying on the peak of the explosion, it may additionally unfold lingering radioactive fallout, probably extending into NATO member international locations and Russia itself.

If, as a substitute of an illustration in a distant space, Putin had been to assault a Ukrainian metropolis with a weapon one-third the Hiroshima yield, the ensuing casualties and destruction of property may strategy that seen in Japan, for the reason that corresponding radii of injury could be about 70 p.c of that seen in these atomic bombings.

Whereas not one of the above situations is at the moment doubtless, neither are they far-fetched. Barring situations of an imminent Russian defeat, one other humiliation just like the lack of the Russian flagship Moskva or rising home discontent in Russia at a stalemated struggle — Putin has no logical purpose to provoke the usage of nuclear weapons.

However wars are very unpredictable, and there are ample precedents in historical past the place a nuclear demonstration has been thought of, starting with america.

In Could 1945, weeks earlier than the profitable take a look at of the primary atomic bomb in New Mexico, former President Harry Truman’s advisers considered, briefly, the choice of a innocent however spectacular demonstration of the revolutionary new weapon as a substitute for its navy use, in hopes of compelling Japan to give up. For sensible causes — there have been too few bombs within the U.S. nuclear arsenal, and a few feared a dud — the demonstration choice was by no means offered to Truman.

However the warning shot concept would floor once more and be taken extra critically. Through the 1961 Berlin disaster, former President John Kennedy was offered with the choice of firing a nuclear-tipped missile at Novaya Zemlya to indicate American resolve. Israel has additionally thought of a nuclear demonstration; previous to the Six-Day Conflict, in Could 1967, Shimon Peres proposed detonating a nuclear gadget over the Sinai desert to go off the battle. Six years later, the Israelis once more briefly entertained the notion of a high-altitude nuclear warning shot to power an finish to 1973’s Yom Kippur Conflict. In 1981, with the Chilly Conflict once more heating up, Secretary of State Alexander Haig — a former NATO supreme allied commander — let slip that “there are contingency plans within the NATO doctrine to fireplace a nuclear weapon for demonstrative functions …”

There’s little doubt {that a} nuclear demonstration is an choice that has been thought of within the Kremlin. This opens the query of what could be the most effective U.S. or NATO response. It’s our view that if Putin fires a nuclear warning shot within the Ukraine struggle, President Joe Biden ought to resist strain to reply in sort and keep away from any choices that might result in an escalating nuclear alternate. As a substitute, the president ought to rally the nations of the world in a common condemnation of Putin for breaking the nuclear taboo and taking probably the most harmful first step towards a nuclear struggle. The U.S. and NATO may additionally reply by use of non-kinetic means like cyber warfare. For Biden, no matter what Putin decides, partaking Russian forces in direct fight ought to solely be a final resort.