The U.S. retains primacy—economic and military might, bolstered by alliances

Yet if this narrative is not baseless, it is overstated. For the idea that the era of American primacy has passed—that we are now entering or have already entered a truly multipolar world—is far from the truth. By virtually all key measures, the United States still has substantial, even massive, leads over its closest competitors. In 2015, the United States claimed a nearly $18 trillion GDP that was more than $7 trillion larger than China’s, and it possessed a per capita GDP (a crucial measure of how much money a government can extract from its citizens to pursue geopolitical ends) roughly four times that of China. In the military realm, U.S. annual defense spending is still roughly three times that of China, meaning that for all the talk of Beijing catching up to Washington, the absolute American lead in overall military investment and capabilities is actually getting substantially larger every year.11 Indeed, America’s global lead is probably far more significant than indicated by simple numerical measures like GDP and percentage of global military spending. GDP is a commonly used but problematic way of comparing U.S. and Chinese economic strength. It is merely a snapshot, rather than a fully explanatory measure, of how wealth accrues over time; it does not account for factors such as the damage that China is doing to its own long-term economic potential through the devastation of its natural environment; it understates important U.S. advantages such as the fact that American citizens own significant minority shares in foreign corporations. By a more holistic measure of national economic strength—“inclusive wealth,” which takes account of manufactured capital, human capital, and natural capital—the United States was still roughly 4.5 times wealthier than China as recently as 2010. Add in the enormous long-term economic problems that China faces, from declining growth rates to a massive asset bubble to a rapidly aging population, and forecasts of coming Chinese economic supremacy become more tenuous still.12 The U.S. military lead is even more extensive. As a recent study by Stephen Brooks and William Wohlforth concludes, although China’s ongoing military buildup presents significant regional challenges for the United States, at the global level there is still simply no comparison. The United States possesses massive advantages in high-end power-projection capabilities such as aircraft carriers, fourth- and fifth-generation tactical aircraft, nuclear powered submarines, AWACS, and heavy unmanned aerial vehicles. These advantages have been amassed over decades, through enormous and accumulating investments, and so it will take decades—if not longer—for China to come close to matching the United States. These metrics, moreover, do not reflect the other, more intangible advantages that the U.S. military possesses—the years of recent experience in complex operations, the extraordinarily high levels of human capital, the flexible command-and-control structures that permit initiative and adaptation. “Rather than expecting a power transition in international politics,” Brooks and Wohlforth write, “everyone should start getting used to a world in which the United States remains the sole superpower for decades to come.”13 Finally, any consideration of global power dynamics must consider the role of allies: The United States has dozens of them, whereas China and Russia have few, if any. (Those that they do have, countries such as Belarus and North Korea, make up a veritable international most-wanted list.) America’s allies give it geopolitical leverage, diplomatic influence, and military access that other countries can only envy; they add enormously to the overall weight of the Western coalition of which Washington remains undisputed leader. As of 2014, the United States and its core treaty allies in Asia and Europe accounted for roughly three-fifths of global wealth and global military spending—a share that was moderately diminished from twenty years earlier, but still very impressive by nearly all other historical comparisons. There may come a time when U.S. primacy has vanished or diminished to the point of strategic insignificance, but that day is still a long ways off. And so rather than abandoning a grand strategy that has worked well over the past 25 years, America should instead work to sustain and reinvigorate that grand strategy for a period in which its primacy remains impressive, even if more contested than before.