The United States becomes ever more deeply involved in the territorial disputes between China and several neighbors over small islands in the South China Sea. That is especially true regarding the bilateral spats involving Manila and Beijing. In an August 2013 visit to the Philippines, Secretary of Defense Chuck Hagel declared that the U.S. alliance with that country was “an anchor for peace and stability in the region.” Earlier this month, the United States and the Philippines reached agreement on a new security accord that will allow U.S. forces to use bases in the archipelago for maritime operations. The formal, high-profile signing of the new agreement is expected to take place during President Obama’s April 28–29 visit. 

In addition to giving U.S. forces enhanced access to Philippine bases, the new pact is certain to lead to another boost in Washington’s military aid to Manila. That will continue a noticeable trend. The United States had already allocated $50 million in such assistance for 2014, more than double the amount in the previous year, even before negotiating the most recent agreement. Moreover, U.S. naval activities in and around the Philippines have soared. According to Reuters, there were 149 visits by U.S. Navy ships in 2013, in contrast to a mere 68 in 2012. Although Philippines leaders continue to insist that the new security accord will not include a “permanent presence” of U.S. forces, the frequency of such naval visits may render that caveat a distinction without a difference.

Although no official on either side will admit publicly that the growing security ties are directed against China, there is little doubt that they are. Reuters correspondent Manuel Mogato notesaccurately that the pact will “raise the level of protection against China, which has strengthened its naval presence in disputed areas in the South China Sea after seizing control of Scarborough Shoal in 2012.”

That trend—and its anti-China focus—has been building for some time. Indeed, the U.S. military’s attempt to re-establish a robust presence began not long after the Philippines Senate voted in November 1991 to evict U.S. forces from Clark Air Base and Subic Bay Naval Base. The initial foot in the door occurred in 2000 with an agreement allowing the U.S. military to train Philippines troops, ostensibly for anti-terror operations.

Since then, Washington has missed no opportunity to emphasize the importance of its bilateral defense treaty with Manila. While attending an economic summit in Bali in November 2011, President Obama went out of his way to highlight his devotion to that alliance and pledged to strengthen the relationship. Chinese officials considered his comment worrisome because it immediately followed Secretary of State Hillary Clinton’s strongly pro-Philippines statements regarding the rival claims in the South China Sea. “Any nation with a claim has a right to exert it,” Clinton said during a visit to Manila on November 16, 2011, “but they do not have a right to pursue it through intimidation or coercion.” She added that “the United States will always be in the corner of the Philippines and we will stand and fight with you.” The Obama administration backed up such rhetoric in early 2012 with a decision to deploy additional “anti-terrorism” troops to that country.

Such uncritical backing of Manila is worrisome, given the deterioration in relations between China and the Philippines in recent years. Tensions flared in the spring of 2012 when the Philippines deployed several ships around Scarborough Shoal (which China calls Huangyan Island) to strengthen its claim. Beijing reacted harshly to that move, gradually sending numerous fishing vessels and naval patrol boats to the area and eventually taking control of the shoal. An editorial in China Daily accused Manila of being “obsessed with playing the role of troublemaker in the South China Sea.” The latest episode, the editorial added, “shows Manila is determined to drag Washington into its maritime dispute with China. By seeking backup from the U.S. in its quarrel with Beijing, Manila has ignored the goodwill shown by Beijing and is trying hard to complicate the issue.” 

Matters have become even more contentious since then. The latest upsurge in tensions began earlier this year when the Philippines filed an unprecedented arbitration case—over Beijing’s strenuous objections—regarding South China Sea territorial claims with the United Nations’ Convention on the Law of the Sea. That case is still pending. Just last month, Manila asked for international arbitration of the dispute. Chinese officials are furious about those maneuvers, and Beijing has escalated the confrontation. In March, Chinese naval units established a blockade in an attempt to prevent Manila from provisioning and reinforcing troops that it had stationed on Second Thomas Shoal, yet another disputed South China Sea islet.

Washington has developed a worrisome habit of supporting small, vulnerable, and unpredictable security clients. The addition of tiny NATO members on Russia’s frontier is one example of such unwise behavior, the risk of which is now underscored as tensions rise between Moscow and the West. Backing the Philippines in its territorial feuds with Beijing is another example of a potentially reckless commitment that might lead to tragedy. 

Some policy experts deny that supporting Manila and other claimants in the South China and East China seas is a strategy that could entrap the United States in conflicts where important U.S. interests are absent. Jeffrey Ordaniel, a scholar at Tokyo’s School of Security and International Studies, National Graduate Institute for Policy Studies, asserts that because “$5.3 trillion in trade passes through the South China Sea every year, $1.2 trillion of which is U.S. trade, the significance of the dispute between Manila and Beijing cannot be underestimated.” Ordaniel adds that doubts about the solidity of the U.S.-Philippines alliance “are more likely to embolden China to use force,” because “Manila has a weak military and a significantly lower deterrent capability.”

But the converse danger is inherent in the U.S. commitment. The promise of support from a superpower can encourage weak states to adopt positions they cannot possibly enforce on their own. And Washington has only limited control of the actions that an emboldened client might take against a more powerful adversary. 

The United States does have some important interests at stake in the South China Sea, most notably keeping the navigation routes free from interference. But that is only one aspect of overall U.S. interests in East Asia. Maintaining a cooperative relationship with China and preventing the onset of a confrontation with that rising great power is the most crucial interest. Getting mired in parochial disputes over uninhabited islets is not worth antagonizing Beijing. Yet that is what Washington is doing by expanding its security ties with Manila and backing that country in its increasingly tense standoff with China. U.S. leaders badly need to reconsider the course they have adopted.