If you want to catch the United States off guard, that would be the time to do something.
You may remember earlier in the Obama years, FEMA and the FCC conducted a mandatory test of the national Emergency Alert System. While the National EAS system is based on the same system that gives you warnings of tornadoes and such things, the National Alert is different in several important ways:
Carrying national alerts is mandatory, immediate and automatic. No matter what is going on, the President has immediate and complete control – not only radio and TV, but SiriusXM, DishTV, DirecTV, your local Cable TV system, and now your mobile phone. Once the Internet of Things is built, It is logical to think that the light bulbs in your home will start flashing in special colors to get your attention.
The non national EAS alerts are generally coordinated by state broadcast associations and state agencies who designate certain stations that can be reliable hubs. The activate signal “beep scratch scratch… Had this been an actual emergency” is relayed from big stations to small stations. While stations at the end points must log local tests, they don’t have to break into live programming to air the test nor are they required to carry actual warnings live or at all.
So Wednesday is a partial national test. The real national EAS message will go out, but only to 22 selected states. The one and only real national test went poorly. Message distribution works differently for the entire country since it is more complicated.
A few regional broadcasters have a special responsibility called being a Primary Entry Point. Upon receiving the header for a national alert, the PEP connects to a central communications bridge controlled by the White House and broadcasts the alert outward until (hopefully) every broadcast outlet in the country is standing by to hear the White House announce something really really important. This capability was not used on 9/11, but the pretense that EAS is useful carries on. Realistically, there is no national event that would be less severe by warning the public. If Russian ICBMs are incoming, 8 million people trying to flee New York City will just kill a lot of panicked people and prevent actual emergency responders from doing useful things.
Sit back and enjoy. Remember – bright flash, duck and cover.