Economics of Brain Drain
For a long time the word "brain drain" was used in India over the people leaving to other countries for better opportunities. The phenomenon was described with an emotional sentiment, suggesting non-payment of dues, that those who are born in this country have a duty to lead a sub-standard life here as opposed to a better life in some other countries. No one bothered to think why people were moving to other countries.
US has been the most popular destination for smart people all over the world to move to. People found it a refreshing change to the repressionist regimes in their own countries.
Another local brain drain has happened in the recent past which, it seems, people have failed to notice. This brain drain is towards Bangalore. People from all over the country are migrating to Bangalore for better opportunities.
So what was common to US and Bangalore apart from job opportunities. The common factor was that people are welcoming towards immigrants, towards people of different race, color, language.
A stark contrast to Bangalore is Chennai, where even if people know your language, they would not speak it, and would rather see you have a hard time communicating. The result is that no one wants to migrate to Chennai, and many of the talented people from Chennai have moved to Bangalore.
Also, thanks for Bangalore, many of the people who migrated to other countries earlier and now returning back to the country, with a lot of money to invest in Indian business.
A similar example in the international scene is Germany. Germans are in general hostile towards foreign people. As a result they are facing a slow down in the economy.