when you say Kashmir was a Hindu and Buddhist state, it sounds like a joke. Hindus came to power in Kashmir after they destroyed Buddhists. Like in India. Islam spread in Kashmir through peaceful activities of Sufis.
And Kashmir belongs to its people, and not any religion. It is Kashmiris and not Islam and Hinduism who will have Kashmir. In any case what business is it of yours. Aren't you living your life properly in your home. Is any Kashmiri taking your land. They are asking for their own land, and a state, which they will have.