Robert Kagan, in a dramatically titled article, “Backing into World War III,” is upset that Donald Trump is thinking of abandoning the foreign policy consensus of the last 70 years and conceding Russia’s sphere of influence or dominance of Ukraine, Poland, the Baltic Republics, Eastern and Central Europe and China’s influence or dominance of Asia, in both cases reducing or perhaps even closing off American trade and influence.
For the United States to accept a return to spheres of influence would not calm the international waters. It would merely return the world to the condition it was in at the end of the 19th century, with competing great powers clashing over inevitably intersecting and overlapping spheres.
These unsettled, disordered conditions produced the fertile ground for the two destructive world wars of the first half of the 20th century. The collapse of the British-dominated world order on the oceans, the disruption of the uneasy balance of power on the European continent as a powerful unified Germany took shape, and the rise of Japanese power in East Asia all contributed to a highly competitive international environment in which dissatisfied great powers took the opportunity to pursue their ambitions in the absence of any power or group of powers to unite in checking them.
The result was an unprecedented global calamity and death on an epic scale. It has been the great accomplishment of the U.S.-led world order in the 70 years since the end of World War II that this kind of competition has been held in check and great power conflicts have been avoided.
It will be more than a shame if Americans were to destroy what they created—and not because it was no longer possible to sustain but simply because they chose to stop trying.