brain drain and reverse brain drain

In not such distant past, our elders used to fret about brain drain, indian talent going abroad leaving behind the motherland the place that nurtured us etc etc. Now circa 2000 onwards we laud the resolve of our expirate brethern for coming back to india, investing here, and giving back to their motherland what they owe.
Since time immemorial, our scripture ascribe motherly attributes to the place we are born in(hindu scriptures). we are taught that the place where we are born is our janamboomi, matribhoomi, karmabhoomi and maransthala (place of birth, place of nourishment, place of work and place of death).
However true this may be in the times of Mahabharata and Ramayana, In the preseant times where we can go around the globe in a day tops, how much of these beliefs are valid?
Looking at the phenomenon of brain drain and reverse brain drain in this light let us see why the former happened and is the latter and different from it
In circa 1960s 1970s and 1980s india was shaping up as a nation. We were rebuilding the tatters left behind by the british raj. We needed a stable economy, dependable infrastructure and a powerful army(courtesy our neighbours). These 30 years were the years nation was being built. A lot of young ones left at this time due to the lack of opportunities(read no infrastructure or economy and constant b0rder skirmishes did not help matters either). They went abroad, lived their american dreams and their descendents got to call america, europe et all their homes.
In 1990s when internet and IT happened, the whole world took notice of the fact that this third world country has a potential; its vast researves of educated manpower.Soon indian economy started to grow at unparalled rates,then came bpo and then post bust things are looking good again. The expirates who were now well settled abroad saw this as a golden opportunity to invest in india and decided to come back. What has ensued and been called reverse brain drain is nothing but a classic example of herd mentality where people are following the footsteps of others. Of course polititcans have been quick to pounce on this opportunity to bring in the dollars with the last government claiming the slogans of India Shining and this one going ga ga over Bhartiya Pravasi Divas
So in totality brain drain and reverse brain drain can be seen as a same phenomenon; the very basic human instinct of following opportunities.