You just described a couple of chapters from Fall or Dodge in Hell novel by Neal Stephenson. In there, someone manufactures this exact story nuking Moab, UT, an

You just described a couple of chapters from Fall or Dodge in Hell novel by Neal Stephenson. In there, someone manufactures this exact story nuking Moab, UT, and it goes viral with huge repercussions around the world for markets and politics. Eventually someone sneaks in and realizes nothing has been nuked. However, a big portion of people resolutely refuse to believe any evidence to the contrary and continue to claim that Moab is a radioactive wasteland for decades later.