For most of modern history, Europe has been America’s “Significant Other.” For the past half century an alliance between the two has dominated world politics. How long can this alliance be expected to last, and in what form? How well does it fit the world likely to evolve in the 21st century?
The present close relationship was not inevitable, as a study of its history indicates. Throughout the 19th and early 20th centuries the transatlantic relationship was governed by American “isolationism.” This amounted to a diplomatic trade-off where the United States refrained from being drawn into European power politics and European states refrained from intervening in the Western hemisphere. The trade off held until the world wars of the twentieth century. Of course, the US was hardly unaware of Europe over this long stretch. The United States was after all, a nation whose population was based primarily on constant European immigration. Events in Europe like the Potato Famine, the Revolutions of 1848 or Italian unification had major consequences for the flow and character of America’s imported population. Immigration reproduced in the United States something like Europe’s own diverse patchwork of vigorously competing nationalities. But nationalist cohabitation in America was not always peaceful. New immigrants often arrived with their old antagonisms intact. Absorbing this rich diversity peacefully has been a Herculean task for the American Republic.