An Anti-Japan demonstration in China.The long-standing dispute between Japan and China over a chain of uninhabited islands, called the Senkaku Islands in Japan and the Diaoyu Islands in China, has surged to an alarming extent. And the Obama administration has foolishly made the United States a party to that emotional, dangerous feud.

Controversy over the islands has simmered for decades with periodic flare-ups, but matters escalated in April 2012 when firebrand Japanese nationalist Shintaro Ishihara, governor of Tokyo, proposed that the government buy three of the islands from their private landowner to discourage any Chinese moves to implement Beijing’s claims. The situation became even uglier in mid-August when fourteen Chinese activists landed on the islands and were arrested by Japanese authorities. Shortly thereafter, ten Japanese activists, including five Tokyo assembly members, landed on the largest island. That move produced large, angry demonstrations in several Chinese cities, with vandals overturning and damaging dozens of Japanese-brand automobiles.

Another spasm of violent demonstrations, which the Chinese government seemed to encourage, erupted in mid-September in response to the Japanese cabinet’s decision approving the purchase. Protests occurred in more than fifty Chinese cities, with rioters again overturning Japanese-brand cars, publicly destroying televisions and other electronics products, and burning the Japanese flag. In several instances, attacks were directed against offices of Japanese corporations. The security environment became so dangerous that several major companies, including Panasonic, Canon, Honda, Mazda, and Toyota, shut their offices and factories in China for several days.

Public anger also is boiling over against the United States because of its status as Japan’s ally. One incident even led to protesters surrounding the car of the U.S. ambassador as he returned to the embassy compound in Beijing.

Tensions are clearly on the rise between the two governments. Beijing canceled a ceremony marking forty years of relations with Japan. The Chinese government also sent several maritime patrol vessels to waters near the island chain to reinforce China’s claim, and at least two of those vessels entered an area that Japan explicitly considers its territorial waters, leading to Tokyo’s vigorous protest. Vitriolic language is becoming commonplace. Chinese vice premier Li Keqiang asserted that Japan’s stance on the islands constituted “outright denial” of World War II’s outcome against fascism and that it posed a serious challenge to the postwar international order.

The Senkaku/Diaoyu quarrel is potentially dangerous to the United States. Secretary of State Hillary Clinton stated in 2010 that Washington’s 1960 defense pact with Japan covers the Senkakus. Assistant Secretary of State for East Asia Kurt Campbell was equally definitive in September 2012, stating bluntly that the disputed islands were “clearly” covered by the treaty, which obliges the United States to come to Japan’s aid if attacked.

The Obama administration’s policy on the islands dispute is both contradictory and foolhardy. Even as she applied the defense treaty to the Senkakus, Clinton insisted that the United States takes no position on the substance of the dispute. But that stance makes no sense. By insisting that the mutual security treaty includes the Senkakus, Washington implicitly regards the islands as Japanese territory, so U.S. officials are prejudging the issue—a point that the Chinese have noted.

And by indicating that Japan could invoke the 1960 treaty in the event of a military incident involving the Senkakus, the Obama administration is encouraging, whether deliberately or inadvertently, the Japanese government and public to be more assertive regarding the dispute. Japanese officials, pundits and policy experts seek to box in the United States on the issue. A September 24 report by the Japan Institute of International Affairs, which has close ties to the Foreign Ministry, demonstrated that point all too clearly:

In the light of historical facts and based on international law, it is clear that the Senkaku Islands are an inherent part of Japanese territory. In this connection, it must be noted that the U.S. has unquestionably treated the Senkaku Islands as Japanese territory—as evidenced by the US’ exercise of its administrative rights to the Senkaku Islands as part of Okinawa under Article 3 of the 1951 San Francisco Peace Treaty and setting up firing/bombing ranges on these islands, and by the US’ explicit agreement in the Agreed Minutes for the 1972 Okinawa Reversion Agreement that the Senkaku Islands are included within the scope of the territory being returned to Japan under Article 1 of this Agreement. . . .This shows that the US cannot assume a neutral stance regarding territorial rights to these islands.

Backing Japan puts the United States on the front lines of an increasingly volatile dispute. True, a Sino-Japanese war over the issue remains unlikely because of the extensive bilateral economic ties. China is Japan’s largest trading partner, and Japan is China’s third-largest export market—behind only the United States and the European Union. But when nationalist emotions run high, such considerations are not always enough to avoid calamity. Germany and France were great economic partners in 1914, but that did not prevent them from going to war.

The United States needs to take immediate steps to reduce its exposure. Since Japan effectively controls the area around the Senkaku Islands, Tokyo would interpret any military move by China to challenge that control as an act of aggression, and Japanese leaders would certainly invoke the defense treaty with the United States. U.S. leaders must not wait for such an event to place America in an inflexible position.

President Obama should overrule the State Department’s interpretation of the 1960 defense pact and make it clear to Tokyo that, regardless of the positions Washington has taken over the decades regarding the islands, the United States is not about to risk going to war over some uninhabited rocks. It is important to take that step before a crisis erupts.

Ted Galen Carpenter, a senior fellow at the Cato Institute, is the author of nine books and more than five hundred articles and studies on international affairs. He is also a contributing editor to The National Interest.