China. China is not an enemy of the United States. Nor is China a friend. Analysts often use euphemistic terms like "rival" or "potential challenger" to describe the regime's relationship to the United States, and no label quite captures a country that is the world's most populous, has the a rapidly growing economy that is already the second largest, and an expanding military that is rapidly moving from third-class to first- rate. China's leadership is both nationalistic and cautious, unchallenged yet suffering from declining legitimacy, eager to establish the country's standing in the world yet prickly and at times obstructionist in solving global problems like climate change or regional problems like Syria. No one knows what China will become in the years to come, but historians may look back at the next four years as the period that determined the nature of the relationship between the twenty-first century's two greatest powers. Greatest threat? Maybe not. Greatest challenge? Quite likely.
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