It is something of a cliche to cite the popularity of curry as evidence of the success of multiculturalism. Those hungry for a metaphor for the benefits of immigration delight in explaining that curry is a British dish. The fact is used to illustrate how Asians have happily fashioned a very British way of being Asian.
This argument first gained traction just as Asian films, books and fashion were starting to make an impact on mainstream culture. It did not seem polite to point out that it was not only curry that was a British creation: the very word "Asian" was also cooked up in this country. It went largely unnoticed at the time but, as I discovered while making a radio documentary, there has been a sharp rise in the number of Asians who are rejecting the label in favour of a religious identity. This growth in religious affiliation is greatly significant and offers both challenges and opportunities for wider society.
The term Asian was coined in 1948 by British administrators working in colonial Kenya to describe citizens of newly independent India and Pakistan. It was brought into this country 20 years later with the arrival of Kenyan Asians. Their arrival coincided with a British civil rights movement that was heavily influenced by the US.
Those fighting for racial equality here believed their cause would gain if all people of colour fought under the single political term "black". During the 70s the immigrant communities settled and began facing different cultural questions. Describing them all as black no longer felt useful. Thus the word Asian, which had been a bureaucratic classification, was promoted to a cultural term.
Pakistanis, Indians and Bangladeshis realised that it was an expedient phrase but Asian continued to gain mainstream currency with the success of films such as East is East and programmes like Goodness Gracious Me.
It became cool to be Asian. Despite its fragile origins Asian seemed to be solidifying into something that was clear, distinct and tangible.
It took a catastrophe to remind us that the word obscured as much as it illuminated and to expose just how much it hid. The impact of 9/11 on the US and international security is well known. Less noticed has been its impact on Britain's Asian communities. Among the first victims of violence after the attacks on New York and Washington were not Muslims but Sikhs, targeted for their prominent beards and turbans. September 11 changed the type and nature of racial abuse - instead of "Paki" the new term of abuse became "Bin Laden" and "al-Qaida" and the abuse was motivated not by race, but by religion. Hindus and Sikhs, frustrated at being mistaken for Muslims, resolved to assert their own religious identity. In doing so they were sending a message to the rest of the country: we had nothing to do with terrorism and riots - that's the work of those trouble-making Muslims.
For the Muslims, September 11 prompted a resurgence of interest in Islam with many choosing to embrace their religion as a response to seeing their community vilified and demonised.
The advantage of an identity rooted in race was that it was usefully vague for fighting the big battles against discrimination. Where they had a common interest or enemy, all communities could march under the Asian flag.
But even before the terrorist attacks, the diversity of achievements, assimilation and experience among the Asian communities was threatening to undermine its effectiveness. Hindus and Sikhs were not only outperforming Muslims in education and employment but, because their religion did not forbid alcohol, they were often better integrated.
If Muslims, Hindus and Sikhs are defining themselves by their religion, does it matter to anyone outside these communities? The briefest glance at recent news events would suggest that it does. The complaints from Hindus about the use of a statue of Lord Ganesh as a weapon in Coronation Street and the furore over the performance of Behzti - the play that offended some Sikhs - imply that an exclusively religious identity can be problematic.
And this is the critical question. Is this new religious identity part of an overarching plural identity, or is it exclusive and separate? Put more bluntly, it is a choice between either wanting religion to be a part of an identity or only being defined by religion and arguing that it is more important than any national identity.
How you define yourself tells others a lot about you and who you think you are. Britain's Hindus, Sikhs and Muslims were long defined by others in terms of what they were not: not white, not black, not British. Now, for the first time, identities are being forged from inside the communities and with confidence. These identities emphasise religion but do not necessarily imply disloyalty to being British.
The great danger, however, is that an identity that emboldens the individual can also threaten the wider society. The challenge to ensure that does not happen is one for all Britons - be they Christian, Hindu, Sikh or Muslim.
· Don't Call Me Asian is on Radio 4 tonight at 8pm