I found it on the internet!
Lede: Use the latest terror incident. Or one from a couple of years ago. Weakest lede: “I went to a conference.” None of these need involve actual dirty bombs or the threat of one. Emphasize that they could have.
Intro: Warn that the most dangerous substances are enriched uranium and plutonium. Those words get more attention than “hospital radiation source”. Explain that these substances are not what would be used in a dirty bomb, but rather a fission bomb. Embellishments of mushroom clouds are optional but will aid in choosing a photo for the story. You can find incidents of attempted sales of such materials, but do not mention that they are of small amounts, hundreds or thousands of which would be needed for a fission bomb. Do not mention that the only buyers were the law enforcement officials conducting stings. Bring in names of terrorist groups. Low-enriched uranium may be mentioned if you imply that the terrorists can enrich it.
Body: Now you can introduce the idea of an actual dirty bomb: damage by explosives, dispersal of radioactive material, panic in the streets. Include a sentence pointing out that deaths are likely to be minimal, explosion damage nothing like the damage from a fission explosion you described in the previous paragraph. This gives the appearance of responsible reporting. Then point out that people are likely to panic because of all the scary news about dirty bombs and radioactivity. Ignore irony. Do not consider the issue of how to disperse material, which is too technical. Use the words “radiation” and “radioactivity” and emphasize the difficulty in cleaning up after a dispersal bomb.
Optional: The actual probabilities of any of these things happening are very low; play down modifiers that indicate this. Subordinate them or put them at the end of sentences if your editor insists on accuracy. Work in the term “weapons of mass destruction” or “WMD” for extra credit. Wrap up that it’s just a matter of time before a dirty bomb explodes in a major city.
DO NOT INCLUDE: That enrichment of uranium requires precision equipment and skilled operators. That uranium is an extremely poor choice for a dirty bomb. That radioactive sources are being replaced in hospitals by accelerators, which have no radioactive materials to steal. That the purpose of President Barack Obama’s Nuclear Security Summits has been to reduce the amounts of both fissile materials (enriched uranium and plutonium) and radioactive sources and has greatly reduced their availability. If you must mention the summits, be sure to frame in terms of work not done. If you focus on oilfield sources or other sources that contain very small amounts of radioactive material in a form like metal that is difficult to disperse, do not mention that they are unsuitable for a dirty bomb.
Latest in the series. Congrats to David Patrikarakos!
Also, some things I wrote earlier with a link to an article from the template. There must be thousands out there.