The Chinese Spy Balloon Is Down. Now The Fallout Begins.

When a Chinese spy balloon was shot down off the coast of the Carolinas this afternoon, fighter jets deflated a diplomatic crisis. The balloon entered the continental United States on the eve of Secretary of State Antony Blinken’s now-canceled visit to China. Despite China’s insistence that it was a civilian meteorological balloon, and expression of “regret,” the U.S. Departments of Defense and State quickly confirmed that it was a surveillance balloon and a violation of international law. China is undermining the rule-based international order—and doesn’t want to admit it. To reassure an anxious public and maintain the diplomatic high ground, the United States must emphasize how China is undermining the international legal order the United States seeks to protect.

Nations have used balloons for intelligence and surveillance purposes since the 18^th century. They were a popular method for intelligence collection during the American Civil War. Today’s high-altitude balloons (HABs) offer a far cheaper method for intelligence collection than space satellites. The United States has employed HABs during recent military exercises to increase maritime domain awareness and identify potential threats—in full accordance with international law and permission of foreign nation-states.

China’s HAB initially entered U.S. airspace over Alaska, exited into Canada, and then re-entered near Idaho before being spotted by civilians over Montana on Thursday evening. It appeared to be equipped with solar panels and controlled by radio. Its belly containing its equipment was the size of three school busses. To the author’s knowledge, it is unclear whether the balloon was controlled or simply moving with the wind.

China has unequivocally violated international law by sending a spy balloon into U.S. airspace without the express permission of the United States. China—along with all of the world’s recognized states—is part of the International Civil Aviation Organization and a signatory to its underlying treaty, known as the “Chicago Convention.” ICAO is the international organization that creates and monitors international civil aviation standards. Each new standard is negotiated by states and then adopted by ICAO as part of an Annex to the Convention. Upholding these standards is crucial to keeping international travel and commerce safe for the world’s citizens. Anyone who has been on an airplane has been kept safe by these critical international laws.

Legally, balloons are aircraft, and subject to the same requirements of other aircraft—even when they operate at high altitudes. Every state has exclusive sovereignty of the airspace above its territory. States do not agree on the exact altitude where airspace ends, but all proposals demarcating sovereign airspace from outer space begin at altitudes significantly higher than those where HABs operate. The ICAO Convention proscribes foreign military aircraft from flying over the territory of another state without express authorization by special agreement or otherwise. Under U.S. law, such authorization would have to come from the Secretary of State. Other remotely piloted aircraft—to include balloons—cannot be operated across another state’s territory without the express authorization of that state. Civilian unmanned free balloons must follow the same rules—with one important exception. Light balloons that are used exclusively for meteorological purposes and operated in a manner prescribed by the appropriate authority are not subject to the same rules. This is the likely reason China concocted its “weather balloon” lie: it is the only chance it has to claim that it behaves in “strict accordance with international law.”

Even if China’s balloon veered off course, under international norms, China should have exercised due regard by warning the United States that its balloon had entered U.S. airspace. If the balloon dipped below 60,000 feet at any point, it was subject to additional international safety standards, including a requirement to be lit at night.

China’s lie will deflate completely in the coming days, as the Pentagon learns everything it can from the balloon’s debris. Many questions will likely remain. Was the balloon controlled by the PRC while over U.S. sovereign airspace? Was there really nowhere between Alaska and the Carolinas where the Pentagon could safely shoot down the balloon? Did the PRC send the balloon to coincide with Secretary Blinken’s planned visit? How did a balloon enter U.S. airspace without detection? Why wasn’t the public notified when the balloon was initially spotted over Alaska? If the balloon disrupted U.S. airspace over Montana and the takedown disrupted it over the Carolinas, are current international standards enough to keep us safe? Could such a balloon be armed next time, like the Japanese balloons responsible for the only civilian deaths on continental U.S. soil during World War II—attacks which the U.S. government covered up for years?

If China intentionally sent a trial balloon when it did, its tactics are reminiscent of its use of lawfare elsewhere: exploiting U.S. law-abidingness in order to advance its own strategic aims. The spy balloon put the military in a bind: shoot it down and risk civilian casualties on U.S. soil, or leave it in the sky and risk lost intelligence and political fallout. To the Chinese people (and U.S. politicians who prefer to politicize national security threats rather than addressing them), China can say that it sent a spy balloon to the United States, and we did nothing about it. If Secretary Blinken showed up, he would have come from a Chinese-perceived position of weakness (likely reinforced by self-serving U.S. politicians). If he canceled, China could blame him for doing so.

The United States must counteract this message. In other arenas, the U.S. has been timid in calling out China for its violations of international law. Here, the United States must not hesitate to own its airspace. It must condemn China’s actions and pursue any available legal remedies. Furthermore, it must clearly explain to the American people why it chose not to shoot down the balloon, emphasize that it took appropriate measures to mitigate China’s intelligence collection, and ensure that future balloon incursions are halted or mitigated. While U.S.-China tensions remain inflated, the U.S. must ensure that this balloon popped with the right message.