Oh, dear God ... even I hadn't thought of that one, but (alarmingly) it's a distinct possibility, isn't it?

Even without it being Alexa specifically (although that doesn't mean it won't be Alexa/Cortana/Google Assistant ¹ ), there's the distinct possibility that some sort of "My voice is my passport" nonsense is already place ... along with all the contingent SF/Thriller tropes so beloved of the ̶h̶I̶g̶h̶ low-Q mindset that gets a thrill from how 'clever' the ideas seemed when they were eight years old ².

I can't remember at what stage we covered the suitability of different modalities for communication/control ... or whether it was part of my Psychology or IT studies specifically (probably the latter) ... but one of the things that was covered was the unsuitability of voice in noisy environments — in films the people in the room are always so collected, calmly following orders whilst the two protagonists argue over whether they should follow orders or not ... but, leaving aside the fact that the stress levels in the voices of whoever finally gives the order to launch the nukes/bioweapon//deathray/whatever might well lead to whichever bot it turns out to be refusing to comply with the order because the psyche profile is deemed to be outside tolerable limits (if their voice isn't simply unrecognised), I wonder if the rest of the room will be so quiet ³.

‎

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¹ Operating under a pseudonym, of course.

² Which, developmentally, of course, was only last month, as it happens.

³ At the very least, you'd expect there to be an element of cacophony as various people announce telemetry values, logistics outcomes, tactical projections, etc.