At noon on Friday in Washington, Donald Trump will become the 45th president of the United States. He enters office at a time of dynamic change, not only in U.S. political and economic life but also in the structure of the international system. At this point, how Trump plans to manage and channel changes underway within the United States is somewhat clear, at least in its broad strokes. By comparison, how his administration will approach foreign policy -- whether it will follow through on some of Trump's less orthodox suggestions -- is unknown. There is, as yet, no Trump Doctrine. There are threads of a worldview, and there is an understanding that Trump is not bound by the same ideological commitments as his immediate predecessors. Of the many unanswered questions surrounding foreign policy under Trump, few are more significant than the future of the U.S. relationships with Russia and China....
