Could the war in Ukraine go nuclear?

The successful Ukrainian attack on Russian forces in the northeast Oblast (region) of Kharkiv was a textbook operation. Planning and preparation were conducted over several months in absolute secrecy, with the result that total surprise was achieved.
Concentrating 15 brigades, with up to 45,000 troops, hundreds of tanks and thousands of other vehicles, without the Russians finding out about it, is extraordinary. It was a high risk strategy, which paid off.
Latest reports are that the Ukrainian Army has reached the regional border of Donbas, putting additional pressure on the Russians. Kharkiv would have been, strategically, the least important territory occupied by the Russians, especially since the withdrawal from Kyiv.
Secure (until now) that the war in Donbas was almost over, Russian priority had already shifted to the Kherson Oblast in the south. Indications are that about 5,000 troops were moved from the eastern areas to Kherson within the past two months.
It is a fair guess that many of these soldiers may have come from Kharkiv Oblast. Ukrainian intelligence would have identified this area as the weak link in the chain of territories occupied by the Russians.

Meanwhile, the Ukrainian offensive to recapture the Kherson region of southern Ukraine has been under way for the past three weeks. So far, low-level probing attacks on the Russian defensive outer screen are in progress, along about a 100km front, north and north-east of Kherson city.
The occupied city is on the west side (right bank) of the Dnieper (Dnipro) River. Ukrainian artillery units are reported to be firing on crossing points over the river in the area, to block Russian resupply or reinforcement.
The stated overall aim of the proposed Ukrainian offensive in the south is to drive the Russians back across the river. However, a more ambitious objective might be to destroy the bridges and stop all possibility of the Russians crossing east.
The encirclement and capture of the now estimated 25,000 Russian troops in Kherson would be a dramatic victory for Ukraine. Once the main attack is launched on Kherson city, whether now or in early next spring, the Ukraine war will enter a new and possibly more dangerous phase.
For once, defense analysts are broadly in agreement on the military objectives. The Russians want to use their forces to strike north, from Kherson and Nova Kakhova, cross the Pivdenni Buh River at, or probably north of, Mykolaiv, then advance in two columns, one due west for Moldova, and the other swinging south to attack Odesa from the north.
The Ukrainians want to recapture Kherson city and push the Russians back to the east side of the Dnieper. In preparation for the counterattack, the Ukrainians have been shelling the bridges and ferries on the river.

There are now diverging views among defense analysts on what happens next. Andrew Bustamente, the former CIA analyst, in a recent podcast interview by Lex Fridman, had no hesitation in predicting that before the onset of winter, in November, the Russians will launch a successful offensive from the Kherson area, capture Odesa, and also link up with Russian forces in Transnistria, Moldova.
On the other hand, General Richard Barrons, former UK chief of defense staff, gave an optimistic assessment of Ukraine’s capability of recapturing Kherson city, and the lands up to the Dnieper River, before the winter sets in.
Barrons, also in his recent
article mentioned the threat of Putin ultimately “going nuclear” if he faces a strategic defeat in Ukraine. By “going nuclear”, Barrons means Putin might use small TNWs (tactical nuclear weapons) which would not physically affect areas beyond the borders of Ukraine.The difference between TNWs and strategic nuclear weapons is often said to be that TNWs are designed to win a battle, while strategic nuclear weapons are designed to win a war.
If the Ukrainians intend to retake Kherson now, they will have to concentrate a significant ‘mass’ of forces in order to breach the Russian main defenses. In the Kharkiv attack, the Ukrainians caught the Russians on the hop and, as mentioned, were able to concentrate without being detected. That won’t happen in Kherson.

If Russian artillery cannot break up the Ukrainian attack, they really will have only three options, dig in and hope for a successful defense, abandon Kherson and stage a risky withdrawal across the River Dnieper, or use one or two TNWs to break up the Ukrainian attack.
If the Ukrainians disperse their forces to avoid presenting a concentrated target, they will not achieve the necessary mass for a successful offensive. If they concentrate their forces, most likely to the north and west of Kherson, they would be very vulnerable to TNW strikes.
Back in 1945, when President Truman decided to drop the (15-20kt) atomic bombs on Hiroshima and Nagasaki, his main concern was to save the lives of American soldiers. Without the bomb, the full-scale invasion of Japan would have cost up to a million US personnel killed or wounded.
Similarly, should disaster face the Russians at Kherson, President Putin might consider the same option, and use less-lethal TNWs to save the lives of Russian soldiers. Nevertheless, this is the first time, so far in this war, that serious consideration could be given to using the ‘nuclear’ option.
Over the years, many analysts argued that you could use TNWs without the war escalating to using strategic nuclear weapons, such as the 100 megaton bomb, that could well herald an ‘extinction event’ for the planet. Others disagree, with the view that, to avoid defeat, a losing belligerent could well escalate to the strategic level.
During the Cold War, the concept of MAD (mutually assured destruction) meant what it said on the tin. Both sides were fully committed to going nuclear if the other used them first. It was the ultimate red line.
By accepting the MAD policy, the US and the Soviets committed themselves not to use nuclear weapons first. However, the Russians have modified their nuclear doctrine in recent times, allowing for first-strike use for certain strategic scenarios.

Today, the Russians have smaller and more sophisticated TNWs, such as the Iskander missile which can deliver a conventional warhead, or a nuclear warhead with a selectable yield between 5kt and 50kt. Some of the new scenarios in the revised Russian nuclear doctrine are imprecise and ambiguous.
Moreover, the destruction of the Ukrainian force, would greatly facilitate the Russian planned offensive to cross the Pivdenni Buh River. The Russians must surely be tempted to go nuclear, if only to save the lives of so many of its soldiers.
The US’s policy of dealing with a Russian nuclear attack in Ukraine is very similar to the US’s policy on dealing with a Chinese attack on, or invasion of, Taiwan. Both scenarios will provoke an undefined ‘overwhelming response’. Since no one really knows what that means, welcome to the concept of ‘strategic ambiguity’. For the moment, the US has lost its political will to lay down redlines.
Unthinkable at present, but Ukraine could well be the first country where tactical nuclear weapons are used on the battlefield. Nato, or a US-led coalition of the willing, should have a red line for this contingency. Not having such a red line sends a signal of weakness and indecision to President Putin.
- Colonel Dorcha Lee is a retired defense analyst