Authored by Hal Brands, op-ed via Bloomberg.com,

GDP and military spending matter, but so do networks of allies and "resilience"...

Ever since the U.S. reached the pinnacle of global power after World War II, Americans have worried it wouldn’t remain there. Waves of “declinism” rolled across the country after Sputnik in the late 1950s, the Vietnam War, the oil shocks of the 1970s, the rise of Japan in the 1980s, and the Iraq War and the global financial crisis of the 2000s.

Now, amid a global pandemic and at the onset of a long struggle with China, the question of American decline has taken on renewed urgency.

The trouble with these debates is that power is as elusive as it is essential: It can be devilishly hard to measure outside of major war. (In war, it’s easy: Who won?) Recently, though, several innovative studies have sharpened our understanding of what power is and how to measure it — studies that are mostly, but not entirely, reassuring for a status-obsessed superpower.

Traditionally, measures of power focused on attributes such as population, energy consumption and production of steel or other indicators of industrial strength. In the information age, these indices tell us relatively little about whether a country can get its way in world affairs.

It is still common, though, to assess power through blunt measures like gross domestic product or military spending. Analysts who argue that Beijing is overtaking the U.S. habitually note that China’s GDP may soon surpass America’s. But GDP is a snapshot of activity rather than a measure of overall wealth. Some countries that spend massively on military power, such as Saudi Arabia, are quite useless in projecting it.

So how can we determine the balance of advantage in a long rivalry? The groundbreaking academic work is giving us better answers.

The first category focuses on refining our grasp of economic and military might. Michael Beckley of the American Enterprise Institute (where I am also a fellow) has developed a model that measures net power rather than gross power by accounting for things such as security costs (“the price a government pays to police and protect its citizens”) and production costs (how much it costs, in material and environmental degradation, to build that coal power plant).

He finds, not surprisingly, that the U.S. fares far better than China, an authoritarian state with vast internal security costs and a prodigiously wasteful approach to stimulating growth. Similarly, it is critical that American per capita GDP dwarfs China’s, because that means the U.S. has more wealth left over, after it feeds its population, to pursue global influence. Other work has better accounted for the way wealth accrues over time, and found that the U.S. will still have far more overall economic power than China even after China’s GDP eclipses America’s.

The second category better captures the reality of “network power.” In a landmark paper published in 2019, Abraham Newman of Georgetown University and Henry Farrell, my colleague at the Johns Hopkins School of Advanced International Studies, argue that the centrality of the dollar to international financial networks — which persists, despite decades of handwringing about its decline — gives the U.S. outsized coercive leverage. Scholars have also affirmed something that policymakers have long understood: America punches far above its own weight in global affairs, because of the network of military, economic and diplomatic partners it leads. China has nothing equivalent.

The third category accounts for less tangible forms of power. For decades, analysts have grasped that soft power — the degree of admiration and emulation a country inspires — matters enormously.

An intriguing study by Ted Hopf of the National University of Singapore, Bentley Allan of Johns Hopkins and Srdjan Vucetic of the University of Ottawa demonstrates that, even though America’s global favorability ratings have plummeted under President Donald Trump, there remains strong global support for democracy and free-market economic policies.

That’s a body blow for an authoritarian, mercantilist China, which, the authors predict, “is unlikely to become the hegemon in the near term.” It also helps explain why European states are systematically turning away from Beijing even amid enormous turbulence in their relations with the U.S.

So does all this imply smooth sailing for the reigning superpower? Not necessarily. The U.S. could deplete its network power by abusing it: Overusing financial sanctions and trade barriers, particularly against allies, could encourage countries to seek ways of opting out of networks America dominates. (The European Union made tentative moves in this direction after the U.S. withdrew from the Iran nuclear deal and threatened sanctions against European companies that did business with Tehran.)

If Washington steps back from leading an open world economy, as it did under Trump, it will lose some of the influence that comes with that role. And if the U.S. damages its democracy at home, as the president is trying desperately to do on his way out of office, that would have vast implications for U.S. soft power abroad.

Finally, there is at least one category of power in which the U.S. is struggling. This would be the concept of “resilience.” A globalized world creates vulnerability to international shocks, whether caused by financial instability, climate change or disease. Resilience is a measure of how well a country can rebound.

The U.S. has demonstrated one extremely powerful form of resilience during the coronavirus pandemic: Its fantastically innovative private sector, in coordination with the federal government, is helping to lead the world out of this nightmare with vaccines developed at, well, “warp speed.”

But the fact that U.S. society is so crippled right now (millions of kids are “attending” school from their living rooms or dining rooms), that per capita deaths are relatively high compared with the toll in many advanced democracies, and that political polarization has prevented Americans from even coming to a common understanding of the threat Covid-19 poses, is more alarming.

According to Bloomberg’s pandemic resilience rankings, the U.S. is only 18th — well behind China — in its response to the pandemic. That’s a flashing red light in an age in which so many transnational threats will test America’s capacity to adapt.

The more we learn about power, the more we realize the U.S. still has great advantages in the contest for global leadership. The longer the pandemic goes on, the more we learn about America’s vulnerabilities, as well.