“There will never be more children alive on the Earth than there is today.”
I think the most likely late 21st C. path is the emergence of empires again, and great-power politics.<p>Rich nations will need to find someway of &quot;finding&quot; their retirement support from poor nations; and poor nations will, typically, experience more mass migrations from changing climate.<p>I suspect this will lead to large armies, high walls, and a certain sort of &quot;human mercantilism&quot; in which young immigrants are a kind of resource.