I wish I had more reputation so that I could flag you for your slander against the good name of CNN! They're always truthful, and national treasure Anderson Cooper is definitely not of Vanderbilt lineage and certainly never interned at any alphabet soups in the past as part of any type of programs named after birds!
The government is here to protect you and would never sprinkle substances on largely populated coastal areas to study the rate of spread of diseases, so why would you ever think they would do anything as benign as test an alert system? Them showing it off to NBC is just a coincidence, either that or a drunk intern of theirs just slept under a desk and thought to call a cab home on it when he woke up.
Hiding under a manhole cover isn't that bad of a call. Just hope that you have enough water and snacks to live for the two plus weeks you'll need to wait for the fallout to settle.
And hey, give Mr. Miyagi a break, I'm sure he's already had to apologize enough for not preventing the new Karate Kid from being made. That level of failure would require harakiri once while he's alive and another seppuku when he's a ghost if he was still living in Japan.
There was that other "fat finger" incident with the alert system somewhere else in the US not too long ago, and that audio was kind of odd, though it kind of sounded like a doom and gloom end times preacher was getting on the wrong airwaves.