The main primary objective of this deal is to keep the rising oil prices under control, which both India and US know and understand very well. India is growing at a rate of 10% with demand for oil on the rise and US economy is heavily dependent on oil. Already oil prices have gone up to US$80 per barrel and US economy being the locomotive of world economy can't afford to help that price going upwards by not giving access to nuclear to a growing country like India. I guess all other strategic & geopolitical objectives are secondary. So considering this, the deal implementation is inevitable with both sides compromising for their economy growth on the upswing in the long term.
