President Obama's moving oration at Hiroshima is timely and welcome. His compassion and dignity will be welcome to the remaining survivors that still bear witness to those terrible and unimaginable days in August 1945 when the US unleashed atomic bombs on the cities of Hiroshima and Nagasaki. His reflections on the dangers of scientific and technological revolution without equivalent moral revolution are unquestionably true. His call to pursue a world without nuclear weapons - echoing the sentiments of his Prague speech in 2009 - is important. His call to change the mindset on war and to strive for peaceful cooperation, for a recognition of our common humanity, is vital in today's world.
Yet what is unsaid speaks volumes. The truth is the bombs didn't just drop from the sky - they were dropped by the United States on civilian populations. And the reality is that - contrary to conventional wisdom about the bombing - they were not necessary to bring about an end to the war. It is a recognition of this truth that is most essential. It is essential even beyond an apology, but it is what makes an apology necessary. The 'necessity of the bombing to end the war' is the foundational falsehood of the nuclear age, and it needs to be exposed and finally laid to rest.
By the time the bomb was ready for use, Japan was ready to surrender. As General Dwight Eisenhower said, Japan was at that very moment seeking some way to surrender with minimum loss of face, and 'it wasn't necessary to hit them with that awful thing.'
Churchill himself said: 'It would be a mistake to suppose that the fate of Japan was settled by the atomic bomb. Her defeat was certain before the first bomb fell and was brought about by overwhelming maritime power.'
So if Japan was defeated and ready to surrender, why were atomic bombs dropped on Hiroshima and Nagasaki?
A significant factor in the decision to bomb was the US's desire to establish its dominance in the region after the war. Those planning for the post-war situation believed that this required US occupation of Japan, enabling it to establish a permanent military presence, shape its political and economic system and dominate the Pacific region without fear of Japanese resurgence. But Japanese resurgence was no longer the US's key strategic concern; its main concern, above all, was the Soviet Union in the post-war world, both in Asia and in Europe.
Whilst many leading US politicians, diplomats and military figures thought it unnecessary to bomb Japan, the group around the US president at the time, Harry S. Truman, pressed strongly for it. Secretary of War Henry Stimson, for example, described the atom bomb as the 'master card' in US diplomacy towards the Soviet Union.
This reality, that the bombs were not required to end the war, but that the US played geo-politics with the atomic bombs on Japan, is what makes an apology necessary. Above all, it is time to set the historical record straight.