Hi Gautam, A right question to ask. The Left has supported the govt for the common Minimum Program (CMP) the n deal was not the part of CMP. The 123 agreement with the usa is a agreement allowing the US and its partner countries to supply fuel (Either Uranium or Plutonium) for civilian reactors for power generation. Along with the 123 agreement we have to bind and sign the IAEI (International Atomic Energy Inspections) agreement to ensure that we have a separate civil and military developments. as well as CTBT ( Comprenhsive Test Ban Treaty). only after signing these agreements the 123 will be operational. India has objections to CTBT as this will limit or stop our developments on military activities like the missile and aerospace technology. Practically speaking the engines developed for Missiles are used also in IRSO Launch vehicles. Also similar technology is used to develop aerospace (fighter planes) technology. Secondly India also has objections to Hyde act which is a obligation on the US government to safe guard the N-supply to the 123 agreement binding countries. The 123 agreement also restricts on certain N developments and research. Secondly US will have access to our R&D related to all Nuclear field as a clause of the 123 agreement. Nuke technology is not only used to make weapons and power but has lot of other activities. The Americans might bring almost all the R&D activities of India especially Isotopes and nuke medical research under its scanner.