In the third and last of his reports on the fears of Hindu extremism, Rahul Sarnaik looks at the work of Hindu nationalists in Delhi and a bitter dispute in Rajasthan.
Nationalists point to positive projects, like this Delhi slum school
In a slum quarter in the heart of India's capital, around 30 young children are seated in neat rows in a small classroom.
Their school is one of around 1,400 social and charitable projects run in Delhi by the Rashtriya Swayamsevak Sangh (RSS) - the oldest of India's Hindu-nationalist organisations.
The RSS has often been accused of promoting Hindu chauvinism and hatred of India's minorities - charges it firmly denies.
Its leaders point to projects like this slum school as proof of its benign intentions.
In a country where hundreds of millions of people live in abject poverty, initiatives like this are often badly needed and warmly welcomed.
But RSS critics claim that such welfare and educational activities can mask another agenda - the use of funding generated overseas for more propagandist and potentially more sinister purposes.
At RSS headquarters its spokesman, Ram Madhav, flatly rejects these claims and says they are lies invented by his organisation's enemies.
"Such people can't do anything positive for India," he says. "So they make baseless propaganda which nobody listens to in India. They make these allegations from safety in the West and create a kind of phobia in India."
We came across contrasting pictures of relations between Hindus and Muslims in the state of Rajasthan.
About 400 kilometres south-west of Delhi lies the town of Asind.
Close by the town is an 800-year-old Hindu temple, which attracts pilgrims from a wide area.
Asind's temple - in the foreground the site of the former Muslim wall
Alongside it, until a couple of years ago, stood a wall which local Muslims say they used as a mosque.
They claim that the wall was built with the permission of the local Hindu community, which readily accepted them worshipping there.
But a recent dispute between the two communities led to the wall being demolished.
Local Hindus and Muslims disagree about what happened.
The temple priest, Bodhi Das, holding court on a platform outside his office, says there was never a tradition of Muslims worshipping there.
"It's all about politics. Muslims have created a controversy here, by inventing the idea that there used to be a mosque."
In a nearby village, a Muslim leader, Mushtaq Ahmed, gave his community's version of events.
"There was a wall, which functioned as a mosque. And we Muslims used to go and pray there. The wall was registered as a mosque at the time India became independent.
"The Indian constitution says that religious buildings registered at that time cannot be pulled down. But Hindu extremist groups organised the destruction of the wall."
The dispute continues and relations between local Hindus and Muslims - which were once warm - have been damaged.
The incident illustrates how communities in India have often shared places of religious significance.
Another pilgrimage site in Rajasthan, a two-hour drive from Asind, shows that the tradition of co-existence is still alive.
The Ajmer shrine, where people of many faiths gather peacefully
The shrine of Hazrat Khwaja Moinuddin Hassan Chishty, a medieval Muslim saint, dominates the town of Ajmer and draws followers from across India's faiths, including Hindus, Sikhs, Christians, Parsees and Jains.
One of the thousands of pilgrims crowding into the shrine to invoke the saint's blessing is Hritesh Sharma, a Hindu.
"I pray here every morning and evening, because I've complete faith in the saint," Hritesh says.
"He answers my prayers and makes everything possible. If there were another three or four shrines like this across India, there would be no Hindu-Muslim tension in this country."
Many believe that when extremists do come to the fore, they threaten the co-existence of Hinduism and Islam.
The Hindu-Muslim rioting in Gujarat in early 2002, which left up to 2,000 people dead, is the most deadly example of recent years.
The rioting occurred after 58 Hindu activists were burned to death in a train in the town of Godhra, an attack blamed on a Muslim mob.
The Godhra train attack sparked religious riots in 2002
It was alleged afterwards that members of Hindu nationalist bodies in Gujarat encouraged attacks on local Muslims in retaliation for the killings.
But back in Delhi, Mr Madhav, the RSS spokesman, says that after 80 years of leading the campaign for India to have a stronger Hindu identity, his organisation now seeks to build bridges with the minorities.
"We had six meetings at the very top level with the Christian leadership; three meetings at the very top level with the Muslim leadership, after the Gujarat violence," he says.
"A lot of ground has been covered. We are hopeful that a very much better understanding between these communities will emerge."
The coming months will see national elections in India - it remains to be seen how big a role Hindu nationalism will play in the search for votes.
Secularists believe that India's strength lies in its immense diversity.
But Hindu nationalists feel the country would be more at peace with itself if it were identified far more assertively with Hinduism - the faith of the overwhelming majority of its people.
The question is whether this debate can be resolved peacefully.
That could be a key issue in the development of India for years to come.