Many men came to India not for holiday moons. They came here for business. We have the story of business men became rulers. But our culture allowed them to stay here and get dissolved in the mass. The Muslims you mention are also Indians by constitution and by BIRTH as their forefathers were Indians. I am sure they will get dissolved in due course. Let Unity in Diversity be the slogan. Have you heard of wild elephants. They are brought to the village and tamed. Be calm. Think of India and Indians. Think of solutions in line with the Constitution of India.