More or Less: Behind the Stats - WS More or Less: Could North Korea Wipe out 90% of Americans?

A single nuclear weapon could destroy America?s entire electrical grid, claims a former head of the CIA. The explosion would send out an electromagnetic pulse ? resulting in famine, societal collapse and what one newspaper has called a ?Dark Apocalypse?.

But are hungry squirrels a greater threat to the electrical grid than North Korean weapons? We speak to senior security adviser Sharon Burke and Yoni Applebaum from The Atlantic.

Presenter: Charlotte McDonald Producer: Hannah Sander