It was a literary reference from Fahrenheit 451.
When Montag escapes into the woods, the government kills someone else instead with their version of a drone--a robot hound. They do this on national TV, concealing the fact that this person is not actually Montag. Honor is satisfied, and the government is seen as successful.
Speaking as a cynic, it's possible Obama will engage in a highly-public attack on anyone at all that can be blamed for this attack. For the record, if he finds the real guys I would support such an attack, but I suspect he might not be that careful.
See also "wag the dog" and "aspirin factory."