TEHRAN (Reuters) - Iran would both retaliate and accelerate its drive to master nuclear technology if the United States or Israel attacked its atomic facilities, Iran's chief nuclear negotiator warned on Sunday. Hassan Rohani, secretary-general of Iran's Supreme National Security Council, also told Reuters there was nothing the West could offer Tehran that would persuade it to scrap a nuclear program which Washington fears may be used to make bombs. Asked about a possible attack by the United States or Israel, which have both said a nuclear-armed Iran would be unacceptable, Rohani said: "If such an attack (against Iran's...