WASHINGTON: "Now, I am become Death, the destroyer of worlds," were the words from the Bhagavad Gita that the great nuclear scientist J Robert Oppenheimer said he recalled, as he witnessed the world's first nuclear test, a fearful event in the history of mankind. Shortly after 9am on Friday, just couple hours before he took oath of office, President-elect Donald Trump was handed over the US nuclear security codes controlling the world's most powerful nuclear arsenal that could easily trigger the end of civilization.What went through Trump's mind as he received the codes can't be divined, but the man who handed over the code clearly does not trust him — something he spoke of repeatedly on the campaign trail, citing Trump's hair-trigger temperament that takes offense at almost any perceived slight.Still, Obama has to go through with it as part of the peaceful transfer of power, even as the world's nuclearatariat fretted about Trump's sense of responsibility given his fragile ego.Weeks before such a nuclear transfer was even on the horizon, ten former nuclear launch officers had issued an unprecedented statement questioning whether Trump could be trusted with control of the arsenal. "The pressures the system places on that one person are staggering and require enormous composure, judgment, restraint and diplomatic skill," they wrote. "Donald Trump does not have these leadership qualities. On the contrary, he has shown himself time and again to be easily baited and quick to lash out, dismissive of expert consultation and ill-informed of even basic military and international affairs - including, most especially, nuclear weapons."Trump himself has gone back and forth on nuclear weapons, sometimes saying the US needs to expand its arsenal and at other times saying the world should curtail the weapons. He was reported as asking at one briefing why nuclear weapons cannot be or had not been used. No one has a clue what he really stands for and the general conclusion among the nuclear commentariat is he has never given it much thought or developed or absorbed any ideas or literature on the subject.The physical asset controlling the weapons — a briefcase called the football — is formally transferred from Obama's control to Trump as soon as he takes oath at noon. But the briefing about its use, including the handing over of a plastic card called a "biscuit" which contain the "gold codes" that can authorize the launch of the weapons are handed over from the incumbent to the successor in the hour before.