TODAY IS THE 69th anniversary of the nuclear attack on the city of Hiroshima that killed upwards of 150,000 people.

That bombing and another on the city of Nagasaki three days later remain the only two times nuclear weapons have been used in warfare.

Since then, the attainment of a nuclear arsenal by nations has been one of the primary containment challenges of international diplomacy.

Eight countries are known to have some degree of nuclear weapon capability with a ninth, Israel, widely believed to possess the weapons despite not officially declaring it.

International pressure and treaties aimed at preventing the spread of nuclear weapons have stopped proliferation to a degree, but the technology required to build and maintain the weapons is also a deterrent.

The above video explains the complex processes involved in the making of a nuclear bomb.

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