Ballistic missile defence
Also called: BMD, PAD, AAD · Topic: India's External Relations, 1947-1999: Non-alignment, Wars and Nuclear Policy · NCERT: Beyond NCERT
Meaning
Ballistic missile defence (BMD) is a shield against enemy missiles. It finds a ballistic missile (a missile that flies a high, curved path to its target), tracks it and fires an interceptor (a defending missile) to destroy it before it lands. India's system has two layers. Prithvi Air Defence (PAD) hits targets very high up, outside the Earth's atmosphere (exo-atmospheric). Advanced Air Defence (AAD) hits targets lower down, inside the atmosphere (endo-atmospheric). With two layers, a missile that gets past the first can still be stopped by the second. BMD matters because it can blunt an enemy's missile threat. It also supports India's nuclear posture, which is built on deterrence rather than striking first.
Example
India's own missile Pralay shows the problem BMD faces. Pralay is a quasi-ballistic missile: it flies a lower, flatter path and can change direction in flight. This makes it harder for an enemy's missile defence to predict its path and intercept it. A fixed, curved path is easier to track and hit.
Don't confuse with
- Strategic Forces Command: this body controls India's nuclear missiles, which are offensive weapons for retaliation. BMD is defensive. It only tries to stop missiles that are coming in.
- Quasi-ballistic missile: this is an attacking missile that is built to beat defences like BMD. BMD is the shield it tries to get past.