"he began punching numbers to calculate the probability of such a catastrophe (...) Hellman estimated these numbers: Rate of initiating events: six percent pe

"he began punching numbers to calculate the probability of such a catastrophe (...) Hellman estimated these numbers: Rate of initiating events: six percent per year Probability that an initiating event leads to a major crisis: 33 percent Probability that a major crisis leads to the use of a nuclear weapon: 10 to 50 percent The third probability is hardest to estimate because we have yet to drop a bomb on Russia (or vice versa)." Very impressive calculations Obligatory xkcd: http://xkcd.com/384/ http://xkcd.com/384/