1)
> I've lived in South Bay myself for 18 years and honestly haven't seen this.
Right, this might just be a matter of personal opinion. I spent a few months in Mountain View, I found it oppressively close to being similar to living in India. It was personally a negative thing because I felt like I (being ethnically of Indian origin but not really culturally one) was expected to behave similar to norms in India. Hell, I had a co-worker accuse (tease?) me of being gay because I was wearing fucking Happy Socks [1]. Now, I must emphasize that I am not saying that everyone who is culturally Indian is conservative or homophobic or whatever. However, the norms in that society of what is acceptable behavior are distinctly different from the norms in this society. A huge cluster of people living together just makes it easier for them to bring their societal norms.
[1] http://www.happysocks.com/us/
> but on a second read, I don't think this qualifies) and reactionary ("clans"?).
The word "clan" was used in the sense of people of a certain kinship living together. This may not be immediately apparent to an outsider but I have lived in India and people from different states are drastically different. This self congregation is apparent in neighborhoods there. At least to me.
2)
> The delta in material situation between India and US is far higher than the delta between US and and Singapore. Westerners moving to Singapore aren't escaping grinding poverty.
Sorry. Most of the new Indians that you see are not escaping grinding poverty. If you have enough money to pay for a Master's degree and then work on an H1B, you are clearly not part of the teeming masses of the poor people, you are ultimately an expat.
3)
> There's a large Indian community in Singapore (indeed the very name of the country is in an Indian language) and if you're going to compare Indians moving to the US to another group moving to Singapore (well, perhaps not moving -- they've been there for a long time), this is probably the right comparison to make. I don't see a problem with multi-ethnic states, as long as everyone lives by the same basic laws.
Actually, I think Singapore is a drastically different case when it comes to Indian immigration. For one, immigration laws are diverse enough that you get both classes of Indians, the white collar professionals and the people escaping soul crushing poverty.