A federal judge’s decision this month to stop the U.S. Defense Department from blacklisting a Chinese biotech firm was the latest demonstration of the lopsided legal contest between the United States and China.

The Pentagon had determined that WuXi AppTec, a major pharmaceutical contractor headquartered in Shanghai, was helping to support China’s military modernization and sought to place restrictions on the company. WuXi AppTec responded by going to an American court—and winning.

The ruling was a setback for the Pentagon’s attempts to weaken China’s policy of military-civil fusion, a national strategy to allow its defense sector to capitalize on civilian technologies, but it also exposed a soft spot in America’s armor: the institutions at the core of the U.S. political system can protect America’s adversaries too.

That imbalance extends far beyond one biotech company. From sanctions and tariffs to intellectual property and national security cases, Washington is competing against an authoritarian rival while remaining constrained by courts, due process and rules that its rival is under no obligation to reciprocate.

The latest example follows the Pentagon determining in June that WuXi AppTec was one of 188 entities supporting China’s efforts to modernize its military. The list also included e-commerce giant Alibaba, electric carmaker BYD and robotics firm Unitree for the first time.

WuXi AppTec’s inclusion on the Section 1260H watch list of “Chinese military companies” meant the U.S. military could no longer do business with it, and the restrictions would extend to third-party suppliers next year.

But James Boasberg, chief judge at the U.S. District Court for the District of Columbia, who has clashed with the Trump administration before, said the Defense Department lacked evidence to support its designation of the firm, which earned 72 percent of its revenue last year—some $4.6 billion—from U.S. clients.

The court concluded that the department had misrepresented a portfolio investment in the company as ownership by the Aviation Industry Corporation of China, the state-owned manufacturer of Chinese military aircraft and jet engines.

It made WuXi AppTec the latest Chinese company to defeat the U.S. government, thanks to another part of the U.S. government.

Kyle Chan, a research fellow at the Brookings Institution, said: “It’s a testament to the strength and fairness of the US court system that a Chinese company can sue the US government—and win.”