Liberal countries do want to provide a social safety net for everybody who resides in their territory. That means you can't simply allow all African's to migrate to the country without straining that safety net.
That would assume that all African's who would choose to migrate are, overall, likely to be safety net dependent than contributing towards the financial viability of that safety net.
And, evidence indicates that more open migration reduces strain on the safety net - it's in the article.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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