New Delhi: : Stressing the importance of nuclear energy in ensuring long-term energy security for the country, Atomic Energy Commission chairman Anil Kakodkar has once again made a strong case for clinching the civilian nuclear cooperation with the United States, going to the extent of saying that history would not forgive Indian leaders if the deal was not sealed now. ’’Here is a chance, where without compromising on any of our principles, we can achieve our energy security. This (deal) is one of the most promising and viable ways of doing it. History will not forgive us if we don't do it now," Kakodkar said in Bangalore on Friday.