I think some of the people here are against the deal simply because their party opposes it. This is without understanding anything about the deal.
What is wrong in being an ally of the US? All the advanced nations are allies of the US. We should also become friends of the US and benefit from that friendship, financially and technologically.
China also signed a nuclear deal with the US long time back. Could the US change China's policy? No. Only the Indian Lefts are spreading that fear. Because China does not want India to have a similar deal with the US.