Non-strategic nuclear or tactical nuclear (NSNWs) weapons are basically battlefield weapons and used to hit counterforce (Command and control, nuclear facilities etc.) target of enemy and they are used for limited purpose. NSNWs include Artillery, mines, SRM (small range missile), bombers, ships and submarines etc. There is no exact definition of range and yield of tactical nuclear weapons but just that tactical weapons have smaller yield than strategic weapons
During cold war era there was clear distinction between strategic and non-strategic nuclear weapons in term of range and yield. Non-strategic nuclear weapons had low yield and range and were used to target any specific area. But after cold war there is blur line or we can say now there is no more clear distinction between both strategic and non-strategic nuclear weapons as their delivery system, range and yield have been improved. Now they have same capability as strategic weapons and can create huge destruction on large scale.
Russia use term ‘Non-strategic nuclear weapons for its tactical or conventional nuclear weapons. It is clear indication that Russian perspective on Tactical nuclear weapons is far different from American perspective. What is the definition of non-strategic nuclear weapons still there is no common consent on it. But it is the fact that Russian tactical weapons are strategic as they have same capability or yield as one strategic weapon has and some weapons have more destructive capability than the bombs which were released on Hiroshima and Nagasaki. Basically these non-strategic nuclear weapons were not covered in strategic Arms Reduction Treaty START and Intermediate nuclear force INF.
Russia justify its non-strategic nuclear weapons in this way that its survival is under threat due to European countries whom US has provided extended deterrence and there is huge conventional asymmetry vis-a-vis US and NATO countries. Due to this reason Russia wants to keep NSNWs. There is a ratio of almost 3,000-6,000 NSNWs which can be delivered in counter response to NATO or European theatre. Russian stance towards non-strategic nuclear weapons is that she is relying on these weapons to make deterrence effective and to give message to US and its NATO allies that in case of any armed aggression, Russia will use nuclear strike against them.
United States was the first to start arms race as she developed its nuclear weapons and then Russia followed the same suit. In the early 50’s both started to develop tactical nuclear weapons to use in battlefield as there was nuclear rivalry between soviet and US so there was huge competition between both of them. In mid-1970’s soviet was ahead in term of mega tonnage then USA.After the dissolution of USSR, geo-politics had changed the dynamics of the world and according to particular strategic environment soviet adapted the method of limited use of atomic weapons to deter its potential adversary (US and NATO) as soviet was comparatively weaker than US in term of conventional weapons that’s why for soviet this was the only way to curb the crisis. Russia realized non-nuclear but strategic conventional armaments as being of potential use in such scenarios
Throughout the cold war nuclear weapons were central to strategy of the US and Soviet as both states had focused on limited war so both decrease the number of nuclear weapons These Include long-range missiles, magnitude bomb, intercontinental ballistic missiles (ICBMS), submarine launched ballistic missiles (SLBMS) and heavy bombers etc. These were basically to hit counterforce target of enemy forces and side by side they also positioned number of strategic weapons beyond their own zones along with the troops. Respective weapons typically had less Yield and range so they had less power than nuclear weapons. These weapons were used for battlefield to achieve tactical and limited purpose.
In 1987 soviet and the US signed Intermediate Range Nuclear Forces (INF) Treaty, removed intermediate and middle range cruise missiles. But after the disintegration of Soviet Union there was huge security concern and soviet economy was also collapse and the conventional superiority which soviet had on US during cold war but after cold war Russia get weak in terms of technology and conventional weaponry and according to particular geopolitical circumstance the US also alter its weaponry. Due to further advances little attention was given to tactical nuclear weapons or strategic nuclear weapons. It is clear from the fact that in Presidential nuclear initiative (PNI) from 1991-1992, little attention were given to tactical nuclear weapons and in START, non-strategic weapons were also not included.
Non-Strategic Nuclear weapons (NSNWs) during cold war
US Doctrine and military strategy:
NSNWs were installed for protection of the U.S. allies against hostility which was posed by the Soviet Union and Warsaw Pact allies, side by side these weapons were against other adversaries as well. For the US and its NATO allies it was under the strategy of flexible response. According to this strategy, NATO did not claim that they will use nuclear weapons against any sort of attack but they preserved the capability to deter the escalation of war. This was a sort of balance of resolve under which US and NATO influenced the perception of soviet so that soviet don’t escalate the crisis but give up.
As the Cold War was about to an end, NATO recognized that now there is no need of having nuclear weapons at large scale or to defeat ant tactical attack from the side of soviet. As now Soviet is not able to launch full scale war on NATO. Side by side NATO also understand that these weapons would continue to play a crucial political role in NATO’s strategy by putting ambiguity in the concentration of any potential adversary that in case of any aggression NATO can use its nuclear arsenal.
US Force structure:
During cold war US shaped and resize its non -strategic nuclear weapons according to particular security threat environment.US had deployed these weapons on zones of NATO and Asian allies in order to provide extended deterrence. In l970, US started to reduce its non- strategic nuclear weapons about more than 7,000 and in late 1980 NSNWs were less than 1,000.US reduced because its NATO allies were also agreed that less number of weapons are enough for the purpose of deterrence but having a good quality .Now US focus was on upgradation of its arsenals as she was not perceiving any immediate threat from Soviet .Between 1980-1988 US developed and upgrade its nuclear arsenals, which include, GLCM (ground launched cruise missiles) ,IRBM (intermediate range ballistic missiles), SRBM(submarine range ballistic missiles),and also build new bombs for navy but after the collapse of soviet Union, US stopped its modernizing programs and both soviet and US signed intermediate nuclear force(INF) to eradicate all short and medium range cruise and ballistic missiles
Soviet doctrine and military strategy:
Like US, Soviet reliance was also on nuclear weapons as a military strategy. During cold war soviet has doctrine of NFU (no first use) but this doctrine can be changed anytime by any state according to particular circumstances. The other thing was that soviet strategic nuclear weapons were more cohesive than US and these arsenals were also useful in case of any astonishment attack or preventive attack .In 1980, Russia also started to reduce nuclear arsenals as they said that strategic weapons have shattering effects but at the same time they are used for deterrence.
During cold war, Soviet Union had installed number of delivery vehicles to deliver NSNWs (nonstrategic nuclear weapons). In different periods, it installed devices that were so minute that they could adjust in little container, nuclear mines, shells which were used for artillery, short-, medium-, and intermediate-range ballistic missiles, short-range air-delivered missiles, and gravity bombs. The USSR installed these arms on almost 600 centres, some of which were positioned in Warsaw Pact states in East Europe including some western and southern outside of the nation and all over in Russia. In 1991, after disintegration soviet was left with about 20, 0000 of non-strategic nuclear weapons before dissolution of Warsaw pact it was almost 25, 0000 NSNWs. 
Non-Strategic Nuclear weapons after Cold War
US strategy and doctrine
NSNWs are still central to strategy of US and NATO policy and US maintained its doctrine of First use (FU) and US relies on amalgam of conventional and nuclear weapons maintaining both offensive and defensive posture and continue to deter and providing extended deterrence . “New Strategic Concept” which were retained in April 1999 specified, “To defend concord and to prevent conflict or intimidation, the Coalition will maintain amalgam of both strategic and conventional weapons. Strategic weapons make a unique contribution in interpretation the dangers of belligerence in contradiction of the Coalition in numerable and offensive”.
Furthermore, the 2010 Strategic Concept stated more reductions in nuclear weapons, in the upcoming future. The allies are “strongminded to follow an inoffensive world for all, in a way that promotes international stability according to Non-proliferation treaty, and is grounded on the belief of security for all.” Whereas coalition had “affectedly concentrated the quantity of strategic weapons based in Europe” and also reduced the role of strategic weapons in NATO plan.” Besides, the arms control progression “should concentrate on the discrepancy with the superior Russian stocks of short-range nuclear weapons.” so, nevertheless NATO no more watched Russia as an opponent, the coalition deceptively arranged that the discrepancy in NSNWs (Non-strategic nuclear weapons) could generate security apprehensions for some supporters of the coalition.
From side to side, the late 1990s, George W. Bush Government, the United States preserved almost 1,100 non-strategic nuclear weapons in its dynamic stock. Around about 500 were air-delivered bombs organised at centres in Europe. Whereas the rest of arsenals, counting some extra air-delivered shells and almost 320 strategic equipped sea-launched cruise missiles, were apprehended in storing zones in the United States.US has condensed the quantity of its centres in Europe that stock strategic arsenal from over 125 centres in -1980s to 10 centres, in seven countries, in 2000.
Russia military doctrine strategy
In past, 20years, Russia has reviewed its strategic and conventional weapons with succeeding varieties looking to dwelling a huge dependence on strategic weapons. Like, the armed doctrine delivered in 1997 permitted for the use of strategic weapons “in case of a riskto the survival of the Russian Coalition. “Doctrine printed in 2000 prolonged the environments when Russia may be used strategic weapons to comprise outbreaks using weaponries of mass destruction in contradiction of Russia or its partners “and side by side in rejoinder to large-scale hostility exploiting non-strategic nuclear weapons in circumstances serious threat to the security and sovereignty of the Russian Alliance
In 2010, it did not definitely approve the preventive use of strategic weapons. But also specified that “Russia assets the precise to usage of strategic arsenal in comeback to a use of strategic or any sort of additional weapons of mass destruction; biological and chemical weapons in contradiction of her and her supporters, and side by side in a case of an hostility in contradiction of her with conventional weaponries that would place in risk the survival of the state.So, there is little indication that Russia strategies to practise strategic armaments at the very start of a clash, before it has involved with conventional armaments. Russia might recourse to the practice of strategic weaponries first, in ongoing limited war.
Non-strategic nuclear weapons in Russian storage, it is very difficult to get idea about that how many NSNWs Russia possess. This ambiguity originates from various factors: improbability about the quantity of nonstrategic nuclear weapons (NSNWs) that the Soviet Union had positioned and stored during 1991, in this year President Gorbachev broadcast his PNI; improbability about the speed of warhead abolition in Russia; and thirdly, ambiguity almost whether all warheads detached from positioning are still programmed for exclusion. Soviet Union might have installed 15,000-25,000 NSNWs(Non-strategic nuclear weapons) in the late 1980s and early 1990s. Through the 1990s, Russian administrators specified that they had finished the arsenals extractions authorized by the PNIs and had ensued to eradicate weapons at a degree of 2,000 each year.
Russia had also seemingly concentrated the quantity of armed centres that could install nonstrategic nuclear weapons (NSNWs), has merged its storing capacities for these arsenals. According to an estimate, the Soviet Union may have almost 500-600 storing locations for strategic armaments by 1991. By the end of this particular period, this amount may have deteriorated to almost 100. In previous 10centuries, Russia might have additional amalgamated its storing positions for strategic arsenals, recollecting almost 50 in manoeuvre
21st century: Relevancy of Russian Non-Strategic Nuclear Weapons in response to current NATO threat environment
The strategic balance in Eastern Europe turned a dramatic turn following collapse of Soviet Union in 1991. Newly born Russia was far-cry of previous super power. Though threat was gone, but NATO instead of restricting its capabilities and influence continued to expand, ultimately absorbing more states in Eastern Europe. After Global war on terror, NATO-Russia tensions eased down to great extent but after American with drawl from Anti-Ballistic treaty in 2002, Russia decided not to give extra leverage to arms control agreements with NATO, one of it was maintenance of credible fleet of Tactical Nuclear Weapons which in Russian perspective are called Non-Strategic Nuclear Weapons (NSNWs).
Russia is economically far behind from Western Europe and US .Russian has about 30% of world’s natural resources which include precious metals, oil and gas. By exporting these resources, Russia produce a huge revenue but in 2014 after decline in oil prices and sanctions which were imposed by US and European countries on Russia on its defence and energy sectors, due to its annexation of Crimea and these all circumstance lead towards deterioration in Russian rubble . Another aspect is, Russia exported its Gas and oil to European countries and during Ukrainian crisis Russia used gas as a mean to blackmail European states. Europe made 75% of Russian export and it was huge share in Russian economy.After sanctions imposed by US and European Union (in term of technology and shale oil production and other sectors) in response to that Russia cut down its supply of gas to European nations due to which it effect the gross domestic product(GDP) of Russia
European states are now relying on renewable energy resources; fossil fuels and shale oil etc. Now Russia is no more able to blackmail European states to fulfil its own geopolitical interests and European states has freed them from the Russian import of oil and gas. Due to such economic conditions, Russia has only option of non-strategic nuclear weapons for the purpose of deterrence against its adversaries as she don’t has enough to build new arsenals as US. Russian defence budget is just 5% of American defence budget.
Another justification provided by Russians on its non- strategic nuclear weapons is NATO’s drill inside Baltic States, Russia provides another justification of its non-strategic nuclear weapons as NATO is expanding towards eastern European states and Baltic States and it’s a severe threat for Russia .NATO is doing agreements and improving conventional and nuclear competences and deploying nuclear capable missile on Eastern Europe and Baltic states near to Russian territory not only this NATO and US are also supporting oppositions inside Russia. NATO is also agree to support Allie’s forces in term of readiness, training and command and control whereas US pledged under European Reassurance initiative (ERI), in which US will provide security assurance to its European allies, on its eastern border to deter and provide advancing resistance against a Russian conventional attack. But NATO maintained a comparable force in West Berlin to serve same interest as US, and it was fruitful for more than forty years in dissuading a Soviet (Russia) endeavour to alteration the status quo by might or coercion. 
Russia is facing adversary which is far ahead in every aspect; smart weaponry, long range missiles which are highly conventional capable, well trained soldiers, nuclear weapons kinematic and non-kinematic means of warfare etc. In response to it Russia has its non-strategic nuclear weapons and side by side building its offensive and defensive capabilities, conducting military exercises, verified delivery system of nuclear and conventional weapons and it seems that Russia is signalling US that though there is asymmetry between them but still Russia can respond US and her allies with its present capabilities. 
The Russian nuclear arsenal is not just for outdated nuclear deterrence, just to prevent the status quo but it is also to be used as a tool of bullying. At the same time, Russia’s nuclear bluffing has generated the perception that a nuclear attack in Europe is once again possible. And it has upraised concerns about Russia’s supposed “escalate to terminate “strategy – a strategy that forecasts forced threats which include concrete limited nuclear use, to sack conventional war on Russia’s standings 
In a situation that would echo in the West, Russia might decide to slice out territory from one of the Baltic States through amalgam of both conventional and nuclear weapons, opening with an instant conventional interchange to generate a “fait accompli” and will hit counterforce target and in turn it will hit adversary’s capabilities. Russia will try to do limited war but in case NATO react to this strike rapidly and Russia feel its conventional defeat than there is chance that Russia will go for nuclear strike. 
Russia didn’t declare what is its nuclear threshold but Russia has military doctrine of first use (FU) and she can launch attack on NATO due to miscalculation as this is game of perception or misperception.
Withdrawal from the ABM (Anti- Ballistic Missile) treaty by US in 2002.This is also tremendous security concern for Russia as US is building Ballistic Missile Defence (BMD) and US has deployed BMD in Europe and to counter BMD, Russia has deployed non-strategic nuclear weapons. Deployment of missile shield in Europe means that, “there is preparation of first strike capability”, according to Putin. Russia has its Iskandar program in response to BMD and current status of this program is not clear up till now.
Due to lack of precision guided non -strategic nuclear weapons like submarine launched cruise missiles (SLCMs) maintained by space technology, don’t have effective command and control C4ISR (computer, command, control, communication, intelligence, surveillance and reconnaissance).Still Russia needs to work on all of these aspects.
Russian outlook on its Non –Strategic Nuclear Weapons, deal with both of political and military aspect. Non-Strategic Nuclear Weapons have played a central role in the military strategy of Russia against its potential adversary US and NATO after the disintegration of Soviet Union. Russian armed forces still lag behind in term of hi-tech weaponry; unmanned aerial vehicles (UAVs),Precision guided conventional weapons and electronic warfare competences with respect to US and NATO. Russia is relying on old soviet military hardware though she is investing in building new military hardware but full implementation is not happening as Russian economy is weak after its dissolution. Russia has capability to attain limited territory with limited options but to fight with major rival, it will take a long way to go.
Though there is asymmetry between Russia and NATO. Russia is behind in terms of technological development but both are doing tit for tat mechanism like US has deployed BMD in response to which Russia launched Iskander missile though it is short range but can cover eastern European states. Both states are doing this for their survival according to realistic perspective but this is engaging both of them in arms race which is very disastrous as it can instigate crisis.
Agreements like INF (Intermediate nuclear forces), PNI (Presidential Nuclear Initiative) and START treaty didn’t pay attention towards Non- strategic Nuclear weapons which was very crucial to discuss but to different other developments NSNWs were ignored. There are chances that both Russia and US will extend New START treaty but it remains to be seen that whether they will include Non –Strategic Nuclear weapons or not.
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