This “accident” begs the question -
Why have an alert if you have not taken the time to inform the public what actions should be.
Why have an alert if a proper civil defense system has not been set up to be prepared for the aftermath of a real attack?
Why have an alert if there are no shelters prepared for people to go to?
I grew up in the 1950s - once a week we had an air raid siren go off. Because of the “duck and cover” classes we had in school I knew (even as a child) what to do if under an attack. (Would such training saved everyone? No, but I am sure many would have survived by following the simple instructions.
We also had air raid shelters in every public building as well as many private businesses.
A 20 minute window is not very big but if there was a real attack, with prior knowledge many would survive that would die because our government is incompetent (oh, that is right, Hawaii is a one party state run by Democrats - of course it is incompetent)
Some of the signs we saw in every public space on field trips.