In these days of economic woe, potential pandemic disease and widespread civil unrest, it may come as a surprise that so many people around the world still view nuclear conflict as the greatest threat facing humanity.
They do so with good reason. Consider the potential effects of a 50-megaton nuclear explosion, similar to the Tsar Bomba, detonated in October 1961, which shattered windows 900 km away and sent a mushroom cloud rising above the stratosphere.
Global agreements such as the Nuclear Non-Proliferation Treaty (NPT), along with the general sense of goodwill immediately following the Cold War, may have led to the perception that such a weapon would never be used in combat. But there is an increasing realization that we cannot breathe easy just yet.