On August 6, 1945, the nature of global warfare changed forever when the United States air force dropped an atomic bomb on the Japanese city of Hiroshima.
The explosion had more power than 20-thousand-tonnes of TNT.
Tens of thousands of Japanese people died in the initial attack. Radiation sickness caused the total to soar to at least 140,000.
The attack was ordered by US President Harry S. Truman. He argued that the nuclear bomb was necessary to force Japan to surrender - and end World War II.
But critics say the US should never have dropped the bomb, and 70 years on opinions are still strongly divided.
On Inside Story we ask whether dropping the bomb was morally or militarily justified?
And could there be a repeat?
Presenter: Nick Clark
Michael Penn - President of Shingetsu News Agency.
Alessio Patalano - Author, historian and specialist in Japanese defence policy and strategy.
Ariane Tabatabai - Professor at Georgetown University and nuclear security analyst.
Source: Al Jazeera