On every British nuclear submarine, there is a safe. Inside that safe is another safe. And inside that safe is a handwritten letter from the British Prime Minister, to be opened only if the country has been decimated by nuclear war. Host Ira Glass talks with journalist Ron Rosenbaum about these peculiar letters. (7 minutes)
This story includes excerpts from a radio documentary called "The Human Button" (click to listen or right-click to save the file), which originally aired on BBC Radio 4 in December, 2008. For more information visit Radio 4. Ron Rosenbaum wrote about it on Slate and in his book How The End Begins.