This is the Camberwell Submarine.
It's not actually a submarine, it's a heating boiler and exhaust for most of the houses around here,
but it's the closest I can find to a submarine that I've got access to.
So, here I'd like to tell you about something you might not know,
which is the "letter of last resort".
The UK has four Trident-class nuclear submarines.
They are our main nuclear deterrent;
we're one of the few countries that actually has nuclear capability. The thing about nuclear war is,
it is monumentally stupid. It involves the deaths of everyone involved
and uncountable numbers of civilian casualties. So the thing is...
if you were the Prime Minister and you know that there are missiles launching towards the UK
and you have four minutes to respond - as was quite possible during the 1980's...
What do you do?
Do you launch? Do you send yours off in return,
knowing that the only thing it can accomplish, knowing that you cannot intercept the incoming missiles,
the only thing that you launching can accomplish is killing more innocent civilians?
Do you launch, do you take the retaliatory strike that you've always threatened? Or...
do you accept that all you can do at this point is kill more people and not launch?
And more importantly...
What if the Prime Minister is already dead?
What if the second-in-command is already dead?
What if the attack has hit and nothing has gone out to the British nuclear submarines?
Different navies around the world have different ways of dealing with this, and the British way of dealing with it
is just... an almost poetic way of doing things.
Inside every British nuclear submarine, inside a safe,
inside another safe is one of four letters, all identical and handwritten by the Prime Minister.
And every Prime Minister that comes to power, even now, even David Cameron,
one of their first duties is to sit down and hand write four letters
that say to the commander of each nuclear submarine, if all has failed, if Britain is destroyed,
if the Prime Minister is dead, if everyone in the chain of command is dead and you have nothing else to do...
...do you launch?
And if the submarine surfaces and finds that Britain is destroyed -
and one of the tests they use is whether Radio 4 is still broadcasting...
allegedly...
they look in the safe.
They open the envelope, they look at the letter, and that tells them whether they
kill uncountable numbers of people as retaliation
or whether they go the nearest friendly port and do what they can to rebuild.
And that's thing about nuclear war: once it's started, all bets are off.
You may as well just give up because the idea was never to launch...
...it was always to deter.
And that is something you may not have known.
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