I woke up this morning to news of a 'hijacked truck loaded with radioactive materials'.
The breathless reporter provided three facts of note.
The truck was carrying a cobalt-60 source used in radiation therapy for cancer treatment.
Cobalt-60 is not explosive.
Cobalt-60 can be used in making a 'dirty bomb'.
These three facts were scattered across a two minute dissertation on just how horrible a dirty bomb can be and another two minutes on how a terrorist organization with a dirty bomb could...well...terrorize.
What they never bothered to mention, probably because it just isn't that exciting, is that the source from a cancer treatment machine is about the size of a thimble, and if you blew it up and scattered it over an area the size of a vacant lot it would be so dispersed that no one would ever know it was there.
Now, if you had an actual 'truckload' of cobalt-60 you could cause some serious problems. For one thing, you would probably have totally cornered the cobalt-60 market because there probably isn't enough refined cobalt-60 in the entire world to fill a truck so all the applications for cobalt-60 would come to a screeching stop. For another thing if you had that much cobalt-60 all in one place you would need so much lead shielding to be able to actually survive driving the truck that it would be buckling the roadways everywhere you tried to go.