By MAX BOOT
The hardheaded case for President Obama's  foreign policy rests on twin pillars: He is a tough commander in chief who does  not hesitate to slay the nation's enemies, and he is "pivoting" from  the Middle East to East Asia to confront the No. 1 threat to American  power—China. There is some truth to both claims, but their essential hollowness  has been revealed by a little-noticed defeat the U.S. has just suffered in a  place few Americans have ever heard of.
Scarborough Shoal is a minuscule rock formation  in the South China Sea that was discovered by an unlucky British East India  Company ship, the Scarborough, which grounded there in 1784. This outcropping  has been claimed by both China and the Philippines because of the rich fishing  beds that surround it and the possibility of drilling for oil.
You would think that the Philippines would have  the better claim, having built a lighthouse and planted its flag there in the  1960s. The shoal is only 140 miles west of Luzon, the main Philippine island,  well within Manila's 200-mile "exclusive economic zone" as recognized  under international law. It is 750 miles from the Chinese landmass.
Nevertheless, China is trying to assert its  sovereignty over nine-tenths of the South China Sea based on tendentious  historical "evidence" ranging from purported trips by Chinese  explorers 2,000 years ago to a 1947 map issued by China's Nationalist  government and recognized by no other state.
However unconvincing its claims, China is  attempting to make good on them by sending fishing vessels and paramilitary  patrol boats into disputed waters. In early April, a Philippine navy ship tried  to prevent Chinese fishermen from poaching seafood from the area. Two armed  boats from the Chinese Marine Surveillance Agency intervened and a standoff  ensued.
Over the past two months, China sent more than  20 ships to the shoal, including as many as seven paramilitary vessels. The  Philippines' interests were protected by two Coast Guard cutters. The standoff  finally ended, at least for the time being, when the Philippines withdrew its  vessels rather than risk losing them in an approaching typhoon.
The U.S. is bound to protect the Philippines  under the terms of a 1951 treaty. Yet even as our ally was being bullied by  China, the Obama administration adopted a pose of studied neutrality.
The Philippines has offered to submit the  Scarborough Shoal dispute to an international tribunal under the Law of the Sea  Treaty, which both Beijing and Manila have signed. But China refuses, no doubt  knowing it would lose. The Chinese leadership must figure they have a better  chance to assert their claim by force majeure because there is no way a weak  state like the Philippines can stand up to them.
The Obama administration did not orchestrate an  international campaign to rally support for the Philippines. And it failed to  take the most dramatic step of all by not sending an American destroyer or  other warship to Scarborough Shoal. Would doing so have risked war with China?  Hardly. In fact China is the classic bully with a glass jaw.
For evidence, look no further than the tiny  Pacific Island of Palau. In late March, at virtually the same time that the  Scarborough Shoal standoff was beginning, a Chinese fishing vessel illegally  entered Palau's waters. When the poachers ignored repeated demands that they  leave an area designated as a shark sanctuary, police from Palau's Fish and  Wildlife Division opened fire, trying to sink the offending vessel.
The result: one fisherman dead and 25 captured.  A couple of weeks later, under the terms of a deal with China, the poachers  were fined $1,000 each and flown back home. The Chinese must have been furious,  but their diplomat on the scene had nothing to say except "it is a good outcome."
No one is suggesting that either the Philippine  or U.S. navies should have opened fire over the Scarborough Shoal dispute. But  it is a sad day when Palau (population 20,000) is more assertive in standing up  to Chinese aggression than the United States of America. The nations of Asia  are watching carefully and making their calculations accordingly. In their  eyes, the U.S. just became a less reliable friend.
Mr.  Boot is a senior fellow at the Council on Foreign Relations and author of the  forthcoming "Invisible Armies: An Epic History of Guerrilla Warfare from  Ancient Times to the Present" (Liveright).
Wall  Street Journal Opinion
