To be sure, many of the Sykes-Picot borders reflected deals cut in Europe rather than local demographic or historical realities. But that hardly makes the Middle East unique: Most borders around the world owe their legacy less to thoughtful design or popular choice than to some mixture of violence, ambition, geography, and chance.
In a world in which the United States does less, whatever set of calculations, other countries will tend to calculate - to move in one of two ways. Either they will assuage or, to use a more loaded term, appease the strongest power in the neighborhood with all the consequences of that, or they will determine to take matters into their own hands.
Living with a nuclear North Korea could give its leaders the confidence to act more aggressively versus South Korea. It could also, over time, drive both South Korea and Japan, as well as countries farther afield such as Vietnam, to reconsider their non-nuclear postures. The stability of a critical region of the world would suddenly be in doubt.
Terrorism needs to be de-legitimized in the way that slavery has been. Doing so will make governments and individuals think twice before becoming a party to terrorism; it should also make it less difficult to garner support for international action against those who nevertheless carry it out.
The Trump administration has been characterized by adhocracy during its initial months. The initiative limiting immigration is a case in point. The new policy was not vetted fully within the administration - indeed, then-Acting Attorney General Sally Yates first read the decision after the text of the new executive order was published online.