• Credible Minimum Deterrence is the principle on which India’s nuclear doctrine is based.
• It underlines no first use (NFU) with a second strike capability.
• Mutually Assured Destruction (MAD) is another doctrine of military strategy in which a full-scale use of nuclear weapons by two or more opposing sides would cause the complete annihilation of both the attacker and the defender.

More Details:

• India’s nuclear doctrine, first officially enunciated on January 4, 2003 asserts that it intends to build and maintain a “credible minimum deterrent”.
• While adopting a policy of “no first use”, the Doctrine clarifies that India’s nuclear weapons will only be used in retaliation against an attack on Indian Territory, or on Indian forces anywhere, in which nuclear weapons are used.
• India also retains the right to use nuclear weapons in the event of attacks on Indian Territory, or on Indian forces anywhere, in which chemical or biological weapons are used.