This is a hardline version of 'Hindu nationalism' that has been the focus of much attention in recent times. The proponents of Hindutva (I find the term virtually untranslateable, even loosely) are now in government in India- the Bharatiya Janata Party and its wider organization the Sangh Parivar.
The Hindutva brigade in India has argued that the Muslims as invaders should conform to a 'Hindu' way of life, and the more extreme ones suggest that they should all be pushed into Pakistan. Distortions of history aside, the growing danger of the supporters of Hindutva became evident during the Gujarat riots of 2002 when over 2000 people were killed in a few days of carnage in Gujarat. The Chief Minister of Gujarat, Narendra Modi, a hardline Hindutva man, was said to have personally been behind much of the rioting by providing police protection to the rioters.
Proponents of Hindutva also assert the superiority of the 'Hindu way of life' over all else. To the best of my knowledge, this is completely contrary to the basic tenets of Hinduism. Hinduism, to use a cliche, is a 'way of life', rather than a religion. It is perhaps the only religion that you cannot 'convert' into, or that does not claim that is the one true religion. It is also unique in that you may not even believe in God and yet be a Hindu. In the light of this, to assert that there is a single monolithic Hinduism that all must adhere to, is patently 'un-Hindu'.
The philosophy of Hindutva was used to justify the destruction of the Babri Masjid, a mosque erected by the king Babur on 6th December 1992 in Ayodhya on the ground that 'history was being reversed'. The matter is still being heard in the Indian Supreme Court with many of the current ministers in the Indian Cabinet, included in the list of those accused of instigating the 'kar sevaks' who destroyed the mosque.
The Hindutva brigade has also taken heart from America's recent 'war on terror' claiming that here is proof of what they had been saying all along- that Islam is a religion that provokes hate, and Muslims are not to be trusted. Of course, considering that the BJP is in power and India is a key geo-strategic player in South Asia, this has been cleverly used by the US administration to persuade India to support US foreign policy goals. I suspect a mutual back-scratching process is taking place here.
Finally, those who advocate Hindutva also propagate conservative social views- some have insisted that women in India be banned from wearing jeans, have railed against the West for importing their culture into India, and have also called for contraceptive ads to be censored from Indian television screens.
I have written a longer WU on the rise of Hindu Nationalism. Also, please check the entries on Gujarat and RSS for a clearer understanding of the Hindutva phenomenon.