Despite the fact that the post Second World War period witnessed the growth and proliferation of a plethora horrendous weapons of mass destruction such as nuclear bombs, human intellectual ingenuity managed to keep the slide into catastrophe at bay. The idea was proffered, and largely accepted, that these weapons were meant not to fight wars but to prevent them. During much of the Cold War period, when nuclear weapons proliferated, particularly among the superpowers, peace was maintained on the premise of the concept of Mutually Assured Destruction (MAD). Since the key superpowers, the United States and the Soviet Union, had the capacity to destroy each other many times over, rational logic prevented both from initiating a nuclear war. Defence was achieved by deterrence, that is preventing the enemy from attacking with threat of overwhelmingly unacceptable level of retaliation ("nuclear deterrence")

Then in the mid - 1970s the US Secretary of Defence enunciated the 'Schlesinger doctrine' named after him. It held that there could be small scale, limited nuclear conflicts, using weapons with greater precision but lower yield, specifically targeted, gradually escalating to higher levels of warfare. In other words, a nuclear exchange could imply 'limited warfighting' which could also be winnable. The view was that at one point of equilibrium along the escalating curve, one side would capitulate. Design and weapons-production followed theory. Weapons became smaller and more precise. They were tactical with shorter range and more appropriate for battlefield or theatre use. For these very reasons the propensity for possible use increased mathematically, and logically. Sensing this danger leaders negotiated and signed treaties, bringing down numbers of long distance and shortrange ordnances down impressively. The total size of nuclear arsenal came down from much higher numbers to about 13000 strategic and 2000 tactical weapons. Eventually these treaties expired. However, rationality still held sway, and although wars had not ceased. Nonetheless, the danger of a nuclear war seemed to have receded. At least up until now.

The aforesaid discussion largely reflected the extant western theoretical and doctrinal literature. But what about Russia, the successor of the Soviet Union? Briefly Russian thinking in this regard was encompassed in the two concepts of SDERZIVANIE ("nuclear restraint") and USTRASHENIE ('intimidation"). This combination is meant to persuade the adversary that it has no chance of achieving its strategic goals by force. This policy which implies use of conventional and strategic weaponry remains in operation both in peace and war. Nuclear weapons are seen as being only one item in the tool- kit of warfare. It includes the western concept of "deterrence" as well as coercive measures and compellence. It is thus designed to be a multi-domain cross-cutting effort using both soft and hard power. Hence the western perception of the Russian doctrine as "hybrid".

In June 2020, President Vladimir Putin signed Executive Order355 that outlined Russia's current strategic doctrine. It contained a systematized asymmetric approach, underscoring the severity and certainty of "punishment". The document lists a whole series of activities by the adversary that may be constituted as a threat to Russia (and its allies) to be "neutralized by the implementation of nuclear deterrence" (meaning "nuclear weapons"). The order also allows for the use of nuclear weapons not only to counter the enemy's similar capabilities, but also "other types of weapons of mass destruction of significant combat potential of general purpose forces". Western analysts believe this as entailing a wide range of options to introduce nuclear weapons at an early stage of conflict to prevent its spread. In other words, a reconfirmation of the "escalate to de-escalate" strategy.

Additionally, the Russians are said to have in place what is known as "dead hand" system, or the "perimeter". It is designed to automatically initiate the launch of Intercontinental Ballistic Missiles (ICBMs) by sending a pre-entered highest authority order if an enemy nuclear strike is detected by seismic, light, radioactivity, and pressure sensors. It will operate even if the commanding elements are fully destroyed, for instance by a pre-emptive strike. The system is normally switched off, but is supposed to be activated during times of crisis. The current war in Ukraine probably fits the bill, especially when Putin has put the nuclear deterrence on "full alert". In any case, it is said to remain fully functional and can be pressed into service whenever needed. The US does not operate a "dead hand" counterpart, but the National Command Authority has backup authorities in the event of the death of the President and/or of Secretary of Defence.

Presidents Biden and Putin had got off to a what seemed to be a fairly decent start when in a phone conversation in February last year they agreed to extend the New Strategic Arms Reduction Treaty by five more years. By doing so they were reversing the decision earlier of President Donald Trump. But with the Ukraine crisis boiling over right now, that happy moment seems ions ago. In the war in Ukraine whether by tactical design or military compulsion the Russians have eased pressure on other parts including the capital Kyiv and are now consolidating focus on the east, in Donbass and Crimea. One consequence has been a burgeoning sense among western allies that a Russian defeat is possible. Hence the enthusiasm to arm the Ukrainians with deadlier weapons than earlier thought appropriate, or wise. The Russian leadership have been warning that red lines are being crossed. The peace talks in Belarus and Turkey have all but collapsed. The sanctions- noose around Russia is being tightened. We have reached a stalemate. The world is on edge. This is what the great international relations thinker Coral Bell described as a "crisis -slide". As things stand now, one hasty decision, an accidental shooting down of a plane, one bomb reaching the wrong target can bring unspeakable results. The danger is very real that one side may be persuaded that the use of a nuclear device would be "rational". We have climbed high on Herman Kahn's "escalation ladder" to Armageddon. Are we inexorably sleepwalking towards a horrific conflagration?

There must be a rethink by global leaders while there is time. Just as President John Kennedy and Premier Nikita Krushchev walked away from the brink of disaster during the Cuban crisis in 1962, our chance may lie in that bit of history repeating itself. My own long diplomatic career had been devoted to issues of disarmament and non-proliferation. I have never felt as close to catastrophe as I do now. Should good sense prevail, and disaster avoided, we must look to one glimmer of hope in the dark cloud. That is the UN Resolution 72/31 of 4 December 2017 banning nuclear weapons. It will take enormous leadership and courage, and a great leap of faith to commit ourselves to it. They say victors write the history. But a total nuclear war may leave us with no history at all, as there perhaps may be none alive to write it!

Dr Iftekhar Ahmed Chowdhury is the Honorary Fellow at the Institute of South Asia Studies, NUS. He is a former Foreign Advisor (Foreign Minister) of Bangladesh and President and Distinguished Fellow of Cosmos Foundation. The views addressed in the article are his own. He can be reached at: isasiac @nus.edu.sg