What this lefties are doing is just pleasing illiterate people. Left project US as anti Muslims and they know that by just opposing US - India deal they can project themselves as the muslims supporter and those illiterate muslims will be there vote bank. After all muslims in india just supports whoever is oppose to US, Because US is nailing down each Terrorist which is of their religion. Also the left is just a puppy of CHINA. China knows that if Nuclear deals become operationalbe, then India can get more Nuclear fuel for commercial use, that will make India's own Nuclear Fuel available for Nuclear weapons thus can make more nuclear weapon. That itself is an advantage for India. Also China doesnt like India to grow to a level with the help of USA. They want to see India as poor as Other Muslim Countries like Pakistan. See China is even opposed to India getting a permenant UN Security Council Seat. In fact China & Pakistan were the only Countries who where opposed it. They want to prevent any growth in India. So they are using our enemies who are living in India (Read CPI-M) against the Nuclear deal.
