On Feb. 9, when a World Health Organization team pronounced it “extremely unlikely” that the novel coronavirus escaped from a lab, few could have guessed how much traction the lab-leak hypothesis would gain in just a few months. Today, however, governments, scientists and news organizations are treating the possibility of a lab leak as entirely credible — alongside the competing idea that the virus was transmitted naturally via an infected animal. On May 26, for instance, President Joe Biden asked U.S. intelligence agencies to step up efforts to investigate the virus’s origins and produce a report that could “bring us closer to a definitive conclusion” as to which theory is correct. Even the director general of WHO has suggested that his research team’s conclusion may have been too hasty, given the limited access it had to Chinese facilities.

This is a scientific question, but obviously one with extraordinary geopolitical implications. Should proof emerge that the virus came from a research lab, and not (for example) a meat-and-fish market, the discovery would make headlines globally. It might also precipitate a free fall in China’s relationship with the outside world — even if nations simply come to believe that the balance of the evidence suggests that China is covering up a lapse at one of its labs (since a smoking gun may never be forthcoming).

Such a shift in views about the origins of the virus would deal a severe blow to China’s soft power. Awareness of that possibility helps to explain why the nation has been so sensitive about this subject. Chinese officials have not only hotly denied the possibility of a lab leak, they have even downplayed that China was the source of the virus in any way. They have argued that the pandemic had multiple origin points (including India), was spread through imported frozen food or escaped from a U.S. Army lab at Fort Detrick, in Frederick, Md. If the Wuhan-leak hypothesis comes to be seen as true, all of that propaganda would be exposed as such — particularly if a coverup was involved.

China has, until now, enjoyed prestige on the world stage for its containment of the pandemic, especially compared with many Western countries. But if missteps by Chinese scientists were the cause of that pandemic, such praise would quickly fade. The self-proclaimed superiority of China’s authoritarian approach in handling the coronavirus would be severely undercut. (The United States’ successful vaccine rollout has already begun to change the equation.) If it started the fire, how much credit does China get for putting it out more quickly than its neighbors?

Even a belief in a coverup without firm evidence of wrongdoing would be damaging, highlighting the disinformation that’s endemic to China’s authoritarian system and hurting the nation’s reputation as a reliable international partner. There are certainly steps it could take to repair its tarnished image. China might ramp up efforts to send more vaccines overseas; according to a vaccine tracker developed by the Beijing-based firm Bridge Consulting, China has already donated 22 million doses worldwide. But this gesture would take on a very different tenor if a Chinese lab appeared to be the source of the virus. Countries may see this less as altruism and more as the very least China is obligated to do.

Should the United States be viewed as solving the puzzle of the virus’s origins — or shifting the balance of evidence — that, too, would have geopolitical implications. The answer to this question is of utmost importance to almost everyone on this planet: What led to the emergence of a once-in-a-century pathogen that was responsible for the deaths of more than 3.5 million people worldwide and the deepest recession since World War II? President Donald Trump’s stewardship of the pandemic was widely seen as a debacle around the globe. If American intelligence can shed light on this mystery, shortly after the successful rollout of the U.S. vaccine program, it will be another step toward reestablishing America’s reputation for competence.

But there would also be significant downsides if the lab-leak hypothesis comes to be seen as correct — and not just for China. Most scientists who entertain the possibility believe that, if a leak did occur, it was inadvertent and possibly unwitting — even if “gain of function” research exploring how the virus might become more transmissible played a part. But Trump and his supporters have entertained darker theories. (“Did someone do something on purpose?” Trump asked last April.) The former president is now claiming vindication and using the phrase “the China virus” again.

Anti-Asian rhetoric is already common on the right, and it would almost certainly become more virulent. Anti-China sentiment, moreover, would put pressure on Biden. There has been a growing bipartisan consensus that China constitutes the central threat to the liberal international order. With new revelations about lab origins for the virus, the Biden administration might feel compelled to adopt an even tougher approach. Depending on the circumstances, it might impose sanctions on some top Chinese officials, boycott the 2022 Beijing Winter Olympics or even sponsor a United Nations resolution to condemn the Chinese regime.

Chinese leaders would face domestic pressure as well. The Communist Party maintains its legitimacy in part because of its perceived competence at running the economy and other matters. Some Chinese citizens who feel deceived might question — if quietly, at first — whether the party is fit to rule. To defuse the budding unrest, the party might further stir up nationalism, another pillar of its legitimacy, and portray the accusations as just another dirty plot by the United States and its allies.

And such a strategy might work. Because of a successful propaganda campaign, many people in China already buy into the theory that the pandemic started anywhere but their country. “I suspect that in small cities and the countryside, 90 percent of people believe the U.S. is the origin point of the pandemic,” a Chinese scholar told me last year. In a society where access to information remains limited and controlled by the government, it is easy for the state to shut out disfavored views. Just as anti-China sentiment would rise in the United States, nationalism and anti-Americanism could surge to an all-time high in China.

As a result, China might return to what Richard Nixon described in 1967, in an article in Foreign Affairs, as “angry isolation”: It might close in on itself to an even greater degree and act even more belligerently externally. In that same article, Nixon asked whether the United States could afford to “leave China forever outside the family of nations, there to nurture its fantasies, cherish its hates and threaten its neighbors.” As president, Nixon would engage with China, ameliorating this situation. But widespread belief that a lab leak occurred could push China back into the state of alienation he described.

After such a long and devastating pandemic, we are all entitled to the truth about its origins. But with political stakes so high, finding out the facts may not be an unalloyed positive development. At the least, the United States should be prepared for an intense political fallout.

Yanzhong Huang is a senior fellow for global health at the Council on Foreign Relations and a professor at Seton Hall University’s School of Diplomacy and International Relations. He is the author of “Toxic Politics: China’s Environmental Health Crisis and Its Challenge to the Chinese State.”

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