Suppose U.S. President Donald Trump's foreign policy is random. I mean really random: Like random luck, designed only in so far as to fluctuate wildly between different, opposing strategic views.

In this thought experiment, it's not a bug but a feature that the United States is pulling away from a nuclear nonproliferation agreement with Iran even as it seeks to negotiate one with North Korea. Similarly, it's an intentional accident that Trump might replace the realist National Security Adviser H.R. McMaster with the conservative idealist John Bolton.

The point of this experiment is to ask what are the benefits and costs of a random luck foreign policy. It's worth considering, because Trump himself has hinted that his oscillation might be intentional. As he put it recently, "there will always be change" and he wants "to also see different ideas."