By cutting its own deal with China, the Philippines has suddenly changed the calculus, persuading the Chinese to let its fishermen operate around a disputed shoal but setting a worrying precedent for the United States and its hopes of using regional alliances to preserve its place as the dominant power in the Pacific.
What had been a fairly united front against China's expanding maritime claims, stretching from Japan to Malaysia, now has a gap in the southeast corner where the Philippines lies, and could soon have another at the southwestern end, where Malaysia is making noises about shifting its alliances.
The Philippine president, Rodrigo Duterte, is angry with the United States over its criticism of his lethal anti-drug program, in which 2,000 people have been killed, mostly by the police.
The deal between China and the Philippines became apparent over the last week with reports that China had begun to allow Philippine fishermen to operate in contested waters in the South China Sea for the first time in four years, rewarding Mr. Duterte for his friendship with Beijing and his coolness toward the United States.
China has not renounced its claim over the shoal, nor has the Philippines conceded China's claim. But the Philippines' main interest in the territory is fish, and it appears to have gotten that, a victory for Mr. Duterte and his popular defense of his country's important fishing industry.
Nonetheless, in allowing Philippine fishermen back into the waters around the shoal, China, whether it admits as much or not, was complying with the part of the ruling that dealt with the blockade, according to Paul S. Reichler, the Philippines' chief counsel in the case."China has suddenly decided to act in a manner that, in fact, complies with one aspect of the award," he said. "It is a welcome step in the right direction."
For Mr. Duterte, who has vowed to scale back relations with the United States, including possibly denying American forces access to five military bases in the Philippines, the deal on Scarborough Shoal came with little cost.
For China there was also little cost. The Chinese still control the area around the shoal, and it would be tough for the Philippine government to negotiate a full withdrawal of the Chinese from the area, which China has considered turning into an artificial island to create a military base.
At a cabinet meeting next week, Mr. Duterte will hear a report from the Philippine Defense Ministry on whether to continue to allow the United States access to the military bases, including one at Palawan, close to Scarborough Shoal. Mr. Duterte has threatened to cancel the 2014 accord that gives Americans access to the bases, a decision that Beijing would welcome. Termination of the agreement requires a one-year notice by the Philippine government to the United States.
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