Firstly, it is binding only to those nuclear reactors that are chosen as Civilian by the government.
Secondly, India still has an independent security agenda that the deal has no bearing on whatsoever.
Third, India can pull out of the deal at anytime .. we will only lose our supply of nuclear fuel. Of course by then we should be self -reliant for nuclear fuel so it wouldnt really matter.
Its ignorance thats driving the opposition for this deal...period.