We are talking about instigating intolerance, with material consequences. Think genocides, like in the OP and Germany in the 30's.
> you either respect the sovereignty of an individual and
> they are responsible for their actions,
Paradox of Tolerance. [0]
An individual lives in a society. Waiting for some other country to sacrifice their 18 years old to clean up your mess because you insisted that you couldn't possibly know what happens when you normalize intolerance is not so nice. And maybe there is no country who could possibly help your compatriots to get rid of their autocrats, so be careful if you try.
It seems there's always a line able to be drawn from a view one disagrees with to the harm that is caused by not contradicting them, and in my experience this does not correlate with how harmful contradiction of the initial view actually is.
So with regard to the paradox of tolerance, I would say one needs to establish that their opponent's views are actually sufficiently intolerant to intrinsically be harmful - and this is not something one can always trust to be done without exaggeration.
The pointe is that that you the moment you want to prevent the action, you have found the public siding with the action. The war is on the mind, you need to get regular people to hand their keys to the autocrats. Infowars, indeed.
Try stopping Hitler from rounding up Jews. Or try to stop Trump's unlawfulness. You are invariably too late by then.
"too late" is relative. Hitler lost after rounding up the Jews and killing 6 million of them. Or rather, Hitler and his many collaborators, both government employees and civilians, did.
An individual lives in a society. Waiting for some other country to sacrifice their 18 years old to clean up your mess because you insisted that you couldn't possibly know what happens when you normalize intolerance is not so nice. And maybe there is no country who could possibly help your compatriots to get rid of their autocrats, so be careful if you try.
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0. https://en.wikipedia.org/wiki/Paradox_of_tolerance