"We must have the courage to escape the logic of fear and pursue a world without them", Obama said of nuclear weapons.
Other presidents before Obama did not venture to Hiroshima because they did not want to apologize for Truman's authorization to detonate the bomb.
One of the survivors stamped his cane emphatically while speaking to the president.
Fujimoto says it was important that President Obama saw the Peace Park firsthand, which includes a museum depicting the aftermath from the light of the bomb and the darkness of war.
In an emotional moment afterward, Obama embraced and shook hands with survivors of the attack, which exposed humanity to risks the president has said the world must do far more to resolve. A young woman handed the president a wreath, which he laid by the Memorial Cenotaph, a monument containing the names of the dead.
The Hiroshima visit must be a reminder to the next administration that more reductions are not only possible, they are necessary. "And it's a testament to how even the most painful divides can be bridged; how our two nations - former adversaries - cannot just become partners but become the best of friends and the strongest of allies".