To support his hypothesis in The Better Angels of Our Nature that the human race is, in effect, outgrowing war, Steven Pinker amasses considerable cultural evidence that individuals in the developed world, spurred in part by the development of commerce, have grown progressively 1) more interactive -- able to see another's point of view, address her concerns, meet his expectations; 2) more 'mannerly,' i.e. more self-controlled, less gross to others, slower to signal readiness to take violent action or to in fact take that action; 3) more empathetic, able to imagine another's pain, and hence more reluctant to inflict it; and consequently, 4) more moral, in any meaningful sense of the word.
Assuming that this kind of development has in fact taken place, unevenly but unmistakably, it's possible to imagine opposite directions from which this social progress might reverse itself.
One is reflected in the ancient fear that highly civilized elite classes, nations or cultures will render themselves ripe for conquest, or at least dominance by less constrained, more aggressive, tougher rivals, whether from outside or within their own society. Fears of this kind of eclipse might be written off as throwbacks to early 20th century worries, expressed by Teddy Roosevelt among others, that a growing distaste for war would render European or American men effeminate, or to racist fears of a "yellow peril." But leaving race aside, it is not hard to imagine that the competitive drive and rapid development of contemporary China will indeed spearhead some kind of eclipse of western values by "Asian values." It's not implausible that declining relative economic power in the U.S. and Europe would combine with war weariness and the advanced values that Pinker lauds to erode and eventually erase the United States' current enormous military advantage -- before "military advantage" itself becomes obsolete. Nor does it by any means follow that a dominant China or other emerging society or nation would be more advanced in Pinker's sense than western nations are today.
From the other end, there is cause to worry that the international global elite might pull away from the rest of us -- increasing their competitive advantage on multiple fronts rather than ceding it. Perhaps Pinker will deal with the global trend toward widening income inequality later in the book. But that gap is becoming a chasm, and it's hard to believe that personal weatlh beyond the imaginings of Croesus will generate superior empathy or values in the majority of its possessors. Rather, the evidence in the U.S. seems to be that current elites, like almost all elites everywhere, are subject, per Fukuyama, to a perhaps genetic imperative to maximize their advantages and make them heritable -- and that this drive, after having been held in abeyance for a generation or two, is now reasserting itself with a vengeance.
One obviously dangerous frontier in this regard is genetic manipulation. Them that have could in the not-too-distant future make themselves basically a different species from the rest of us, perhaps even immortal. What in current economic rends suggests that they would share that wealth, even if whatever innovations come don't go horribly wrong in their own right?