From Atri in Future Scenarios thread...
In my opinion, to understand India, her history and her civilization, we need to look at the classical concept of Sapta-Sindhu. Although the concept of Sapta-Sindhu has been changing with time,
in all the given times, India's civilization along with her production centres, centres of learning, centres for military and political power and economic growth have been along the Sapta-Sindhus of contemporary time.
In Early Vedic times, the Sapta Sindhu means rivers of Punjab, Saraswat and kabul. In later Vedic period, it also includes Ganga-basin as well (Mandala 10, Nadistuti sukta). By the time of Vishnupuran (around 400BC) the pan-subcontinental view of sapta-sindhu was ascertained. It is included in 7 holy rivers of Ganga, Yamuna, Godavari, Saraswati, Narmada, Sindhu, Kaveri.
I think in modern times, the 7 basins which I have marked in map above marks the centre of gravity for India.
1 - Red - Indus Basin
2 - Red - Ganga basin
3 - Yellow - Krishna-Godavari Basin (I think they should always be considered together because people, rulers, and market of this region behaves in similar way with respect to Indo-Gangetic basin and Kaveri basin)
4 - Blue - Narmada-Tapti Basin
5 - Blue - Mahanadi Basin
6 - Blue - Kaveri Basin
7 - Black - Airavati Basin
It is impossible for the people from basin 2, 3, 4, 5, 6 to progress alone without being bothered by people from basin 1 (Indus valley) and without taking care of basin 7 (Irawati valley). With time (in not so distant future), people from basin 1 and 7 will have to be persuaded (forcefully or peacefully) to join in.
The people from Basin 3 overlook the affairs of people from basin 2 and basin 6. The influence of rulers and market of this region spills over to aforementioned basins time and again. During most of the times, basin 4 and Basin 5 play secondary role to the interaction of basin 2 and basin 3.
Basin 6 is comparatively secluded from the affairs of basins 1,2,3,4,5 and thus has acted as perfect incubation facility for sustained growth (of market and produce). Furthermore, substantial parts of basin 6 are blessed with rains for 8 months, thus making Kaveri valley as one of the most fertile regions of India.
Basin 7 has to be taken into consideration as it acts as a sole gate-way to India for another rising power in Asia, China.
The political unification of these 7 river-basins from source till mouth of the major river and their tributaries is the key towards stable India and world. This entire region of all these rivers is needed to be brought back into the fold of Indic civilization, so that even in case of political disintegration, India will stay..