Having to type out YES or some phrase is a fairly common "Are you really sure you want to do this??" sort of thing. I gather they're also looking at requiring a second person's confirmation which, if practical and very unlikely to make it impossible to send any message, seems reasonable as well.
One reason of course is a combination of alarm fatigue and the fact that software has trained people to just always click yes when an annoying pop up appears.
Another is that people will think the have already clicked the correct thing button. So it’s less “Oh a confirmation box has appeared, let me confirm that I pressed the correct button” and more “stupid computer, of course I clicked the right button, that’s what I want to do!” without realizing they did in fact accidentally click the wrong button.
Any reasonable person typing in “This is not a drill...” would pause half way through. It’s not the same as blindly clicking “Yes”.
Yes, in situations where the message does not fit within a pre-defined list due to an unexpected event. Of course it should still have security mechanism's to ensure that the transmission is properly authorised.
The biggest threat is probably misuse by politicians rather than the poor clerk!
Allowing a separate option for a clerk, maybe with confirmation from a supervisor or other clerk, to send an arbitrary message (with a separate approval chain) would be useful as well. In the Hawaii situation not having that option likely delayed sending out the retraction as they didn't have a built in.
This should also only be used for the real alerts and not the drills/tests otherwise you're training users to blindly type YES.
Maybe changing the challenge to "HOLY FUCKING SHIT YES THERE REALLY IS A FUCKING NUKE COMING AT US SEND THE FUCKING MESSAGE!!!" in the real challenge would work better. Of course, when you have to push the button like that, I'm not sure if you could still type straight ;).
But yeah: how do you properly write a test for a potentially dangerous operation?
Of course they then need a way to test the button...
Have PINs required for certain critical operations and post those PINs in multiple places around the facility. Each PIN is different for each operation. That way the user has to look up the PIN before sending out the "you're going to die" message.
The codes would be per action not per person. So the "send missile threat" activation code would be, for example, 98790 for everyone and the "test send missile threat" would be 16289 for everyone. You'd have to look up what the code was for your message you wanted to send. All test message start with 1 while all real messages start with 9. They could be rotating so employees don't memorize them.
So to send an alarm by mistake someone would need to press the wrong button and also look up the wrong code and also ignore the meaning of the code prefix.
Just an example.
Though maybe just "this is not a drill" would be better/easier.
In any case, your proposal suffers from the flaw that in a real emergency, nobody will have the extra seconds to spare to look up a code, because that would literally be thousands of people dying per lost second, so the emergency codes will all rotate from '99999' through '99999'. And an employee would actually be responsible for changing the codes from '99999' to '99999' every time they are required to rotate.