threat of retaliation it has to be 'credible', as Achin Vanaik emphasises, in order to be 'effective'. This means that 'the capability and the will of the deterrer must not be doubted', resulting in periodic displays of this 'capability' (in Republic Day Parades, for example), apart from a constant update of its technologies. Deterrence cannot afford to get stuck in a time-lag; it has to be persistently competitive.
