Superpower military competition has abated, but the specter of nuclear weapons still adds a completely new dimension to warfare. The destructive capacity of so-called conventional bombs was made cruelly evident in the Second World War. Yet, today, a single, thermonuclear bomb has the explosive power of a million times the largest conventional device, with not only devastatingly immediate consequences but also extremely harmful long-term effects, both at the site of the attack and far away, in time and space (Figure 1).

In Figure 2, the small central circle with a radius of 1.4mm represents the combined area which would have been affected by the total of all the explosives used in the Second World War. The larger circle, with a radius of 100mm, represents the relative destructive power of the nuclear arsenals stockpiled today. This is a terrible and, hopefully, a sobering image.