The twentieth century was in many respects the American century. Having emerged to world power status by 1900, the United States evolved over the next hundred years into the main actor in global politics and, with its Cold War triumph over the Soviet Union, had arguably become the sole global power by the end of the twentieth century.


Associated with this, America’s economy, which underwrote its immense power and prosperity, led the world initially in traditional manufacturing and later in the high-tech industries of the modern era. Furthermore, America’s success had much to do with its capacity to define itself as the land of freedom – the meaning of freedom changed over time but no idea was more fundamental to Americans’ sense of themselves as individuals and as a nation.

The twentieth century appeared to prove the promise of the United States’ eighteenth-century founding that it would enjoy continual progress as the land of freedom and opportunity. Of course, the benefits of this progress were not evenly distributed along racial, gender and class lines. Nevertheless, the United States did make advances in addressing these issues through its civil rights revolution, its women’s rights improvements, and the redistributive policies of the New Deal and Great Society.


The public policies associated with these developments had created significant political cleavages by century’s end. From the 1930s through to the 1970s the Democratic Party and its identification with liberal uses of government at home held the ascendancy and gave direction to the nation’s political course. In the following decades, America turned rightward as antipathy to big government and greater acceptance of market forces gained the upper hand under the Republicans. Whichever party was in power, however, both were fundamentally committed to maintaining America’s global superiority through a powerful military, interventionist foreign policy, and economic diplomacy.

At the peak of its power and prosperity as the twentieth century ended, the United States appears to have entered a new period of relative decline in the twenty-first century. The rise of China threatens its global economic predominance at a time when its domestic economy has only achieved weak recovery from the Great Recession of 2007-09. Its public debt has spiralled and without a fiscal course correction threatens to become unsustainable. For many families, the American Dream has lost its meaning amid conditions of stubborn joblessness, stagnant wages, and growing income inequality.

Meanwhile, America’s immense military 

power has not guaranteed success in prolonged interventions in Iraq and Afghanistan and cannot provide solutions to new international problems, whether pertaining to the Arab Spring or to climate change matters.

In these circumstances, political divisions at home have intensified rather than declined. Some analysts have characterized the recent partisan gridlock in Washington as producing broken government at the very moment when America needs united and effective leadership to address its long-term problems. Today’s Democrats and Republicans appear incapable of bipartisanship because of their polarized views on the role of government, public spending, and taxation.


Despite its problems, the United States remains the most important actor in global politics and its economy’s wellbeing is fundamental to global economic growth. Both candidates in the 2012 presidential election defined the contest as one whose outcome will shape their nation’s development through to mid-century. Its effect on the rest of the world is likely to be no less significant.