It was in the autumn of 1980, at the height of what was known as the Iranian Hostage Crisis, when over 50 Americans had been taken in by Ayatollah Ruholla Khomeini's radical followers in Teheran.

In the US, Jimmy Carter was in deep trouble in the last days of his presidency and anti-Iran hysteria was at its height. I was at the Criminal Court of King's County (Brooklyn), New York City, as a journalism student covering a murder trial. I asked a question of the prosecution bench, and the government's counsel turned around and lashed out, "Where're you from, Iran?" He pronounced it 'eye-ran', just as in a later era George W Bush would say 'Sad-damn'. There was no reporting for me that day in Brooklyn.

The gentleman was of course making the characteristic mistake of the ugly insular American who can be found even in ultra-cosmopolitan New York: that anyone who is white is right, all blacks are former slaves and brown people forever the unreconstructed alien. The worldview of that particular prosecutor has doubtless progressed since the Iran hostage-taking, even as the national ire has been diverted from the Ayatollah to Osama, with a brief diversion at Sad-damn.

Without doubt, following the tide of brown immigration to the United States since the 1970s from Latin America, Southasia and West Asia, Americans are today better educated as to the nature and content of world humanity. But at moments of crisis, the deeply held prejudices will boil to the surface. The 9/11 attacks were such a crisis, and afterwards, people with Muslim names and/or brown skin tone became the targets of venom.

The inability of the occidental to distinguish Osama bin Laden's headgear from the Sikh's turban made life unbearable for a while for sardars all over, and among the first to be murdered by vigilantes in the US after the World Trade Centre attack was a Sikh in Arizona for his 'Middle Eastern appearance'.

The way in which 'Islamic radicals' are seen in the west will have changed subtly with the London attacks of last week, and there will be a simultaneous shift in how all Southasians are perceived outside the subcontinent. The 9/11 attacks were all carried out by young Arab men, mostly from Saudi Arabia. The only link to Southasia then was through Osama's network, which extended to Afghanistan and Pakistan. In the case of the attacks on the London trains and bus, all suspects thus far are of 'Pakistani' ancestry.

Granted, a Great Britain which has seen such overwhelming brown migration since half a century-enough to change the composition of British society-is vastly different from exclusivist America. As a result, there will be much more introspection in London and less of a blame-the-world syndrome evident.

Nevertheless, the discovery of young Southasian Britons as the perpetrators of the terror attacks on Londoners will once again bring to the fore their identification as 'Islamic terrorists' rather than 'terrorists'. Nor will the reaction be limited to brown-skinned people who are Muslim. For who is to distinguish a Pakistani from an Indian, a Southasian Sunni from a Southasian Shia, a Sindhi from a Punjabi, a Bangladeshi from a Gujarati?

Indeed, one must consider the distance or proximity between a young Muslim of 'Pakistani' ancestry living in Leeds and a young Muslim of 'Indian' ancestry living in the same town? We may thus witness a strange situation in which an attack on London's public transport system forces Southasians to consider their own shared natural and cultural heritage-from the colour of their skin (olive to brown) to their accents. General Musharraf's lilt is not that different from that of Lal Krishna Advani's, and now the two even appreciate the same Quaid-e-Azam.

While there are those Southasians of the Himalayan rimland who are considered 'Mongoloid' and 'Australoid', the majority of Southasians are brown 'Caucasoids' who are easily mistaken for one another the world over.

While Southasians have suffered acts of terror often enough, this is the first high profile attack in a western capital by radicals of Southasian descent. It is certain that the worldliness of London, the political clout of the Southasian community in Great Britain, as well as the deeper links between the European island and the subcontinent will not deliver the kind of primitive reaction we saw after 9/11. But there will be a subtle shift in the way that we are perceived and it will once again force Southasians outside Southasia, at least, to consider each other as more similar than dissimilar. Nationalisms cannot get us too far in other hemispheres, howsoever we may treat each other here.