This hack could absolutely get people killed. There are several tweets I can think of from POTUS that would begin immediate military mobilization from an unfriendly country.

Yeah, this could've been very bad. I don't buy that it's a test. Twitter is going to fix this. Probably it's a restriction of the exploit that you don't know the posting account or something.

Or just post some white nationalist call for arm. The US is ripe for a blood bath right now.

You would be surprised. Of course it would be a disruptive tweet, but it would not be a credible threat of war, in reality.

As mentioned in a NYT article, Trump’s account is under “separate lock and key” which I think means it was not vulnerable to this threat. But yeah still super scary. Src: https://www.nytimes.com/2020/07/15/technology/twitter-hack-b...

[bomb_emoji][china_flag_emoji]

That's assuming Tweets actually serve an actual diplomatic function and are not merely marketing/propaganda for voters.

(Also POTUS is not authorized to declare any wars btw.)