The concept itself is simple:
UNDERSTANDING DETERRENCE

• Deterrence occurs when A persuades B not to take an aggressive step by convincing B that whatever the
  anticipated gains he hopes to achieve, the likely costs he will have to face will be higher.
• When A issues a threat, its effectiveness will depend on B’s perception of A’s intent. If B does not take A’s
  threat seriously and concludes that it can be safely ignored, then deterrence fails.
  Deterrence, well it is affective when it is effective.
  To explain with a simple example; A “Scarecrow” in the fields. A ‘Beware of Dogs’ board. Telling a child not to touch
  a hot plate ………. this one however works from the second time onwards.
  In matters military, however, deterrence is more than merely threatening a potential adversary. It demands the
  subtle shaping of perceptions so that an adversary sees the alternatives to aggression as more attractive. Perception
  incidentally is not just about passively receiving information; it’s an active and dynamic process to interpret and
  understand sensory information. E.g when Mahfuz Alam, who is an advisor to Bangladesh’s interim government
  claims that parts of West Bengal, Assam, and Tripura are part of Bangladesh, it is not a threat……. it is at best a joke.
  Deterrence appears simple in principle and a natural strategy to adopt but it is not so straightforward when it comes
  to implementation. Deterrence works best with explicit red lines (Lakshman Rekha), backed by three Cs:
  Credibility, Capability, Communication.
  Credibility: Russia fired the IRBM Oreshnik, capable of carrying multiple independently targetable re-entry vehicles
  (MIRVs) at Ukraine’s city of Dnipro on 21 Nov. The Russian response was credible and the American ATACMS and
  British Storm Shadow fired by Ukraine on Russia were quickly withdrawn to their stables. Notably, without
  credibility, deterrence is simply pretentious bragging.
  Capability: Credibility is in turn rooted to capability: having necessary resources and technological edge to carry out
  deterrent actions – includes advanced weaponry, cyber capabilities, and a strong military. Capability however can be
  dwarfed by a serious imbalance in trade. Countries with large trade surpluses have the power to exert influence on
  trading partners. Large trade dependency is a serious capability vulnerability dwarfing strategic credibility.
  Communication: Deterrence is achieved when the communication is straight forward and unambiguous (stuttering
  and shuffling does not help). It must be consistent and not seasonal. Having allies and friendly neighbours who can
  echo your communications help. Effective communications lie in capability and determination to fulfil a threat.
  Surprisingly Mutually Assured Destruction is historically the most successful form of deterrence.
  During the Cold War, the US and Soviet Union avoided direct conflict despite numerous geopolitical tensions and
  crises. Even in Ukraine the US despite material assistance has refrained from deploying NATO troops and long-range
  weapons to strike deep inside Russia. This is out of fear for the conflict escalating to a nuclear one as threatened by
  Russia leading to mutual destruction. The concept has also kept the Indian subcontinent safe from a nuclear war,
  although it remains a delicate and sobering balance.
  India follows the policy of No First Use (Nuclear) – the threat of retaliation rather than the threat of a first strike.
  The doctrine is part of India’s broader strategy of credible minimum deterrence. No First Use remains a significant
  policy in the landscape of nuclear strategy, balancing the fine line between deterrence and diplomacy. India,
  however, maintains a credible second-strike capability to deter adversaries from considering a nuclear attack ……….
  Not too hot (overkill), not too cold (underwhelming), but just right.

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