It is a shame that it has to last 30 minutes that people were told it was a mistake.
In such critical cases, there should be better drills and software should be tested more thoroughly.
The novel (of which movies exist)
On the Beach is about a nuclear attack in which Australia is about the only place where it is relatively safe.
Because virtually all targets are in the northern hemisphere, so Australia is still relatively safe.
But the biggest nuclear threat is not Kim Jong Un (he should stop his nuclear weapons program anyway), but Donald Trump. Last week the Trump administration declared to make use of nuclear weapons easier. Combine this with the mental health of this 'president'.
And another issue the US where there is a nuclear waste dome built in the 1950s in the Marshall Islands which is a ticking time bomb.
https://www.youtube.com/watch?v=autMHvj3exA