Raids with the purpose of killing women and children don't rate the term "civilisation". From agriculture onwards, having additional hands, especially non-threatening ones, helps whatever the equivalent is of the economy. Even nomadic cultures adopt captive children into their tribe. The only logical example might be a hunter gatherer tribe scratching out an existence in hard circumstances. Tell me, in which way does the UK resemble these?
If we go by your arguments and look for the most primitive cultures around that practice killing women and children, then the reciprocal answer would be to eliminate the threat to us in the same way. Not that you'd really condone that of course, except to snipe at us from a distance like you always do.
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