Just how close have we come to the apocalypse? A lot closer than you might imagine. Just between the years between 1950 and 1980 alone the United States experienced a recorded 32 accidents involving nuclear weapons. That is according to journalist Eric Schlosser, who has documented the many times we've come close to Code Red in his book Command And Control.
There was one nuclear weapons accident in 1961 over North Carolina where a B-52 bomber started to break apart mid-air because there was a fuel imbalance on the plane, and as it was breaking apart the fuselage started to spin. The centrifugal forces on the plane as it was breaking apart pulled a lanyard in the cockpit. And that was the lanyard that a crew member would pull if they were above the Soviet Union and about to bomb.
There were two hydrogen bombs on the plane and hydrogen bombs are dumb. They're machines. When that lanyard got pulled the bombs didn't know they were over North Carolina not over Moscow. One of the bombs went through all of its arming steps, and when it hit the ground there was a firing signal sent. There was only one switch inside the bomb that prevented a full-scale detonation. That would have been a bummer because John F Kennedy had just become President and they literally would have had to evacuate Washington D.C.
Now this particular switch the following year was found to be defective in many of our nuclear weapons. They would have unloaded the weapons from the airplane and realised that the weapons were fully armed because the switch hadn't worked. If one of the defective switches had been in that bomb... it sounds so corny but it would have changed the course of this world.
Again and again, you find examples of hundreds, if not a thousand or more, accidents involving nuclear weapons that could have ended very badly.
The direction which military history has gone since the end of the Cold War has been to very targeted kinds of warfare, drone warfare - and nobody's suggesting that drones are perfect, they're certainly not - but there's a much more surgical approach to modern warfare and in that sense nuclear weapons don't seem to necessarily fit that trend. Do you think nuclear weapons still have a role to play in keeping the world safe? Does the idea of mutually assured destruction still apply?
I think it's more complex. The threat to kill all the civilians of your enemy country is effective. But at the same time it's a psychological threat. And if you get a madman as a leade.r or if you have a group like ISIS or Al Qaeda, who believe that dying on behalf of the cause sends you to heaven, then threatening to kill doesn't have that impact. So in the 21st century nuclear weapons have no purpose whatsoever.
This summer was the 70th anniversary of the destruction of Hiroshima; that was a really crude, inefficient, rudimentary nuclear weapon, and in an instant it killed 80,000 people and knocked down two thirds of the buildings in a big city.
We built, in the Cold War, nuclear weapons a thousand times more powerful than that. The nuclear weapons that Russia, the United States, China, France and Great Britain have are vastly more powerful than that. So I think everyone has to realise that we either work towards reducing the number of these things and eliminating them, or they're going to be catastrophes that make 9/11 - I was in New York City on 9/11, and I saw the aftermath of the destruction of the World Trade Center - that will seem trivial compared to what's possible with these weapons.
Can you ever see a future where we are disarmed, or is it just too complicated, and politically and practically difficult?
I think it's within our power, if not to solve it 100 per cent, then to greatly reduce the danger, and the first step is for people to be aware. These nuclear weapons are out of sight, out of mind, literally. They're in silos underground, they're in submarines under the surface; there are these machines waiting to kill you. It's as simple as that. There are still 16,000 nuclear weapons in the world. They're wired up, they're ready to go and if one of them goes off it's going to be a catastrophe beyond description.