 "President Barack Obama speaks with Japanese Prime Minister Shinzo Abe during their meeting with South Korean President Park Geun-hye at the Nuclear Security Summit PTI")
Barack Obama on Friday became the first sitting US president to visit the site of the world's first atomic bomb attack, bringing global attention both to survivors and to his unfulfilled vision of a world without nuclear weapons.
Obama touched down in Hiroshima after completing talks with world leaders at an international summit in Shima, Japan.
The visit presents a diplomatic tightrope for a US president trying to make history without ripping open old wounds. Obama planned to make a short speech and pay tribute to the 140,000 people killed in the bombing seven decades ago.
But the White House has stressed he will not apologise for the attack, which is viewed by many in the US as having hastened the end of World War II; others have called it a war crime that targeted civilians.
The president also is expected to renew his push for a world without nuclear weapons, an aspiration for which he received a Nobel Peace Prize early on his presidency but has since seen uneven progress.
The White House has said Obama will offer a simple reflection, acknowledging the devastating toll of war and coupling it with a message that the world can - and must - do better.
Here, at this place of so much suffering, where US forces dropped the bomb that gave birth to the nuclear age, Obama will also place a wreath at the centopath, an arched monument in Hiroshima's Peace Memorial Park honouring those killed on August 6, 1945. A second atomic bomb, dropped on Nagasaki three days later, killed 70,000 more.
Hiroshima is much more than "a reminder of the terrible toll in World War II and the death of innocents across the continents," Obama said it on Thursday.
It is a place, he said, "to remind ourselves that the job's not done in reducing conflict, building institutions of peace and reducing the prospect of nuclear war in the future."
Those who come to ground zero at Hiroshima speak of its emotional impact, of the searing imagery of the exposed steel beams on the iconic A-bomb dome. The skeletal remains of the exhibition hall have become an international symbol of peace and a place for prayer.
The president is accompanied on his visit by Japanese Prime Minister Shinzo Abe - a demonstration of the friendship that exists between the only nation ever to use an atomic bomb and the only nation ever to have suffered from one.
