Good question Kamal Puttar. But the answer is pathetic. There is no doubt that Muslim rulers used force and 'lalach' for converting Hindus to dirty Islam but with in Hindu religion, Brhamins are equally responsible for keeping these unfortunate converted people away from Hinduism. Till today the storry is the same. You reform Hinduism, see how these muslims cames back. After all they are tired with that irrational religion.