It may be the case that the most powerful force affecting the human future is demographics.  Will population continue to increase?  That seems unlikely, over the next century.  At some point all societies seem likely to go the way of Europe and Japan, and begin to have fewer than "replacement-level" populations.  This is not necessarily a good thing, at least in the medium term.  Most basically, it will challenge the basic economic model on which modernity has arisen, namely, that of endless growth.  What happens when there's not more demand for more things in the next generation?  We don't know yet.  For a nice overall view of demographics in the past and in the coming century, this piece isn't half bad.

Furthermore, this will have knock-on effects in other ways.  How will youngsters support increasing numbers of retirees?  What about countries that will "grow old before they grow rich"?  Will there be a "geriatric peace"?  What will be the consequences for politics of this move--will the state shift from being a market state (it once was a army state, then added on night-watchman state capacities, and is now a market state), to become a "retiree home state"?  We just don't know.  But consider:

“Governments worldwide have evolved to meet the challenge of managing more people, not fewer and not older. Capitalism as a system is particularly vulnerable to a world of less population expansion; a significant portion of the economic growth that has driven capitalism over the past several centuries may have been simply a derivative of more people and younger people consuming more stuff. If the world ahead has fewer people, will there be any real economic growth? We are not only unprepared to answer that question; we are not even starting to ask it.”

Also, check out the argument in this piece that, as the population ages, it will also become more religious, as older people--people with more life experience, I'm tempted to say--tend to become more religious.  Nor does this seem to be about older people just sticking with their childhood religion--they seem to become more religious as they age.  As the researchers discovered, "In Japan, one of the countries most affected by aging, there are a number of indicators revealing a slowdown of secularization trends and even a resurgence of religiosity."  Interesting...

And finally, take a look at these six maps from Brookings, which reveals that the amazing American diversification has not decelerated in the last 10 years--if anything, it has accelerated and moved beyond the costal/southern border area into the white heartland. I suspect that, once there are significant minority populations in lots of these white states in the middle of the country, some of the racial animus will decline.  (Though the experience of the Deep South and Texas doesn't suggest that is necessarily the case.) Really interesting data here.