The hostility between India and Pakistan could be fuelling dangerous divisions within Indian society.
As tension escalates, many Indian Muslims say they feel under constant suspicion, increasingly alienated from the Hindu majority.
Their sense of unease comes just three months after anti-Muslim violence in Gujarat, some of the worst Hindu-Muslim riots in recent history.
Concern is also growing about the anti-Muslim agenda of ultra-right Hindus.
Dr Rizwan Qaiser, a Muslim and academic focusing on inter-community relations, showed me his Muslim neighbourhood.
He says the area is about 90% Muslim. The remainder are Hindus who have lived here for centuries.
The concept of separate Muslim areas isn't new - but as the threat of war with Pakistan grows, many, like Dr Qaiser, say social divisions and ghettoisation are growing too.
"If I as a Muslim look for a house in mixed locality and approach a property agent, the moment he hears name of Muslim, he would say, 'Sorry, no room for you'," Dr Qaiser tells me.
"Number one you are not given access, number two you fear, number three you're not culturally comfortable - so these are the factors which finally go into making what you call ghettoisation and I'd call clustering together for a sense of security."
Cricket test:
Muslims say the current climate of hostility between Delhi and Islamabad has created a climate of suspicion amongst even close friends.
They feel under constant pressure to prove they're loyal to India, not Pakistan.
"It hurts me a lot, a lot," says Aftab Tayyab, a science student. "I cannot explain to you - it creates a sense of being alienated in this land."
He feels uneasiness from Hindu friends he's known since childhood.
"Whenever there is a cricket match between India and Pakistan - they always think we're supporting Pakistan and not India. Why so? We're as much Indian as they are.
Dr Mukarram Ahmed Mufti "When the tension escalates then this type of question comes more frequently - such as 'Do you support Pakistan?', 'You're going to have a war, what's your opinion about this?'
"I will always support India, why will I support Pakistan? This is our motherland."
His brother, Shadab, says he feels the same suspicion from friends.
"Some of my friends ask me: 'Do you have any relatives in Pakistan? We'll bring them back to India so we can attack Pakistan.'
"This sometimes makes me feel I do not belong to this country or I've been alienated by my friends."
Muslims 'tense'
At Fatehpuri Mosque, in the narrow, chaotic streets of the old city, thousands of Muslims come to worship and to study at the religious school.
But the community is tense.
Dr Mufti Mukarram Ahmed, the imam at the mosque, says he hears constant reports of harrassment by the Hindu majority - which have steadily worsened since the war on terrorism.
"They complain when we are passing through the Hindu areas.
"They say things like: 'Bin Laden is going', 'Bin Laden will be demolished', 'Bin Laden will be no more and the Muslims will be taught lessons'."
The vicious anti-Muslim riots in Gujarat three months ago sparked fresh fear.
Hindu mobs accused Muslims of being pro-Pakistan and ordered them to go back home.
The pleas of Muslims that India is their home are constantly questioned by the Hindu ultra-right.
'Alienation'
Dr Qaiser says the allegations and violence have sent shockwaves through Muslim communities.
"Muslims are terribly shocked, they've developed a strong sense of alienation and they're also fearful about the future.
Muslims have been shouting from the rooftop that we belong to the land as much as they do.
"We are in the process of integration but each time developments like Gujarat take place their sense of belonging to the land, and the system and to the wider society suffers a terrible setback."
That struggle to belong isn't helped by a lack of support from the central government, led by the pro-Hindu BJP.
It's refused to criticise the government in Gujarat - despite a series of independent reports accusing it of complicity in the killings.
For many Indian Muslims, the threat of war with Pakistan is just compounding a growing sense of insecurity and unease.