The triangular chain of atolls and reefs that is the subject of the dispute between the Philippines and China is well within Manila’s economic zone, about 123 miles off Subic Bay in Luzon Island.
But the Chinese government claims sovereignty over virtually the entire South China Sea, and it has drawn warnings from the Biden administration not to provoke conflict as it moves aggressively to prosecute these claims.
In 2016, just as Mr. Duterte was assuming the presidency, the Philippines took its case against China to an international arbitration court, and it ruled in favor of the Philippines.
During his nearly five years in power, though, he has mostly chosen not to antagonize China, hoping to keep aid from the giant neighbor flowing. That stance stands in contrast to how Mr. Duterte has treated Barack Obama and the European Union, which have both been targets of his verbal attacks. Mr. Duterte has acknowledged his profane ways, saying at one point that God had advised him to tone it down.
Last week, Mr. Duterte profusely thanked China for delivering Covid-19 vaccines to the country, saying he was deeply indebted. And on Monday, he appeared to receive his first dose of the Chinese-made Sinopharm vaccine, according to a livestream shared on Facebook by a Filipino lawmaker.
Still, the territorial issues are a red line of sorts for the Philippines, even if Mr. Duterte has at times sounded almost apologetic in explaining his case.