Yesterday afternoon, Barack Obama became the first sitting President of the United States to visit Hiroshima, the site of the world’s first atomic bombing. It was a predecessor of Obama’s, Harry S. Truman, who had ordered the bomb to be dropped at Hiroshima and gave the go-ahead days later for a second device to be dropped on Nagasaki — both events that were a decisive factor in the unconditional surrender of the Japanese to bring the Second World War to an end.

While historians can debate the historical context of dropping the bombs then, the world community has come too far now to ever contemplate the use of nuclear weapons again. Yes, when East and West faced off in the darkest days of the Cold War, mankind was but an order and a press of a button away from nuclear annihilation. And while there appeared to be times that a nuclear strike was imminent — who among us remembers the Cuban Missile Crisis? — thankfully, political and military leaders never crossed that line of no-return.

There is no apology from Obama, though, for the dropping of those lethal bombs. Words of regret and of the lessons learnt are all that now comfort the survivors and the families of those killed and maimed.

If there is a lesson to be learnt, it is one that needs to be remembered by all who possess or seek to possess the power of nuclear weapons — that they can never be used again. World leaders have a duty to all who share this blue planet on its trips around the sun, and for the generations to come, that never again will the genie of atomic annihilation be let out of the bottle. Those who have such weapons must abide by the strictest of protocols. Indeed, it is incumbent upon us all to ensure that these governments are convinced that reducing and ending their quest for nuclear weaponry is the only way forward.

Obama has a proven track record of backing nuclear disarmament in both words and deeds. But events globally now — tensions in Ukraine between East and West; tensions in the South China Sea; and the unpredictability of the rogue leadership in North Korea — make it difficult for any further real progress to be made on nuclear disarmament.

As much as we want a world free of nuclear weaponry, the sad reality is that ever since the US unleashed those weapons in August 1945, regimes and leaders are enthralled by their terrible power.