Amid concerns over North Korea, federal emergency managers are updating disaster plans to account for large nuclear detonations over the 60 largest US cities, according to a US Federal Emergency Management Agency official.
The shift away from planning for small nuclear devices that could be deployed by terrorists toward thermonuclear blasts arranged by “state actors” was discussed on Thursday at a two-day National Academies of Sciences workshop for public health and emergency response officials held at its headquarters across the street from the US State Department.
“We are looking at 100 kiloton to 1,000 kiloton detonations,” chief of FEMA’s chemical, biological, radiological, and nuclear branch Luis Garcia told BuzzFeed News. The agency’s current “nuclear detonation” guidance for emergency planners, first released in 2010, had looked at 1 to 10 kiloton blasts — smaller than the 1945 Hiroshima and Nagasaki atomic bombs that killed more than 200,000 people at the end of World War II. Those smaller size detonations had seemed more reasonable after 9/11, with high concerns about an improvised terrorist bomb.
But last year North Korea tested an apparent thermonuclear bomb with a surprisingly large estimated blast size of 250 kilotons, a “city buster” much bigger than past test blasts and nearly the size of current US intercontinental ballistic missile warheads. The test blast kicked off a new era of nuclear anxiety in the US.