Robert Kagan is a senior fellow at the Brookings Institution. He writes a monthly foreign affairs column for The Post. He is the author of the forthcoming book “The Jungle Grows Back: America and Our Imperiled World.”
Since the end of the Cold War, it has widely been assumed that U.S. foreign policy would follow one of two courses: Either the United States would continue as primary defender of the international order it created after World War II, or it would pull back from overseas commitments, shed global responsibilities, turn inward and begin transitioning to a post-American world. The second approach was where U.S. foreign policy seemed headed under President Barack Obama, and most saw the election of Donald Trump as another step toward withdrawal.
It turns out there was a third option: the United States as rogue superpower, neither isolationist nor internationalist, neither withdrawing nor in decline, but active, powerful and entirely out for itself. In recent months, on trade, Iran, NATO defense spending and perhaps even North Korea, President Trump has shown that a president willing to throw off the moral, ideological and strategic constraints that limited U.S. action in the past can bend this intractable world to his will, at least for a while.
Trump is not merely neglecting the liberal world order; he is milking it for narrow gain, rapidly destroying the trust and sense of common purpose that have held it together and prevented international chaos for seven decades. The successes he is scoring — if they are successes — derive from his willingness to do what past presidents have refused to do: exploit the great disparities of power built into the postwar order, at the expense of the United States’ allies and partners.
At the core of that order was a grand bargain. To ensure the global peace that Americans sought after being pulled into two world wars, the United States became the main provider of security in Europe and East Asia. In Europe, the U.S. security guarantee made European integration possible and provided political, economic and psychological safeguards against a return to the continent’s destructive past. In East Asia, the American guarantee ended the cycle of conflict that had embroiled Japan and China and their neighbors in almost constant warfare since the late 19th century.
The security bargain had an economic dimension. The allies could