Why India is too much concerned about muslims ?

Terrorism in India started from the days of freedom fighting. In continuation, Mahatma as killed by Brahmin groups. Indira was killed by Sikh groups. Rajiv was killed by Lankan Hindu groups, supported by Hindu groups of India to eradicate Nehru Dynasty. All these murders have purely religious motive and supported by their respective religions. But even the murderers are not quoted as terrorists. If any muslim does, the whole community becomes terrorists. Why this double standard ?