Is America’s turn left a turn inward?

In his landmark Foreign Affairs article "The Sources of Soviet Conduct" at the beginning of the Cold War, George Kennan laid out the strategy of containment. He noted how important the example America set domestically - economically, in coping successfully with its internal problems - was to the looming geopolitical competition with the Soviet Union. Yet Kennan did not take the emergence of an America that was a good example for granted. He also noted that, "by the same token, exhibitions of indecision, disunity and internal disintegration within this country have an exhilarating effect on the whole Communist movement."

Thus, one of US foreign policy's great strategic minds made it clear that he believed American domestic politics would have a decisive effect on global politics. Kennan's exhortation for America to set a good example should especially be on our minds today,...