Interesting theory from a military reader regarding yesterday’s plastic explosive detection which, I wrote, turned out to be a false alarm:

Jonah, I would caution that “false alarm” may be an inexact definition of the event. Example: Say the “sprinkler parts” were wrapped in that annoying bubble wrap, and sealed in a box. Before they did that, they took the bubble wrap and wrapped in around a block of C-4 overnight. They then wrapped the parts with the same wrap, and sealed up the box. Now they have some idea how sensitive the screening equipment is and from there they could develop a way to mask the traces. Watch for another “false alarm” soon. If there is one then this was a probe. Just a possibility like the “Flying Immans”.