[Drago]

EAS tests are a regularly scheduled thing (regionally)...nationwide coordinated tests are less frequent:

http://emergencyalertsystem.org/rmt-schedule/

https://www.ecfr.gov/cgi-bin/text-idx?SID=c636ac3c34563b639a56a79954d9eb9f&mc=true&node=pt47.1.11&rgn=div5#se47.1.11_161

https://www.ecfr.gov/cgi-bin/text-idx?SID=c636ac3c34563b639a56a79954d9eb9f&mc=true&node=pt47.1.11&rgn=div5

[C210N]

Thanks for those links.

As near as I can discern now, the only time, evah, the system was used Nationwide was a test on November 9, 2011.

It was not used on 9/11.