Bullying tactics often work if the one being bullied doesn't have the muscle, strength or willpower to stand up to the bully. That pretty much sums up what seems to be happening between China and the Philippines right now. Strategy Page reports:
President Duterte is trying to be realistic in his policy towards China but that seems to be making the situation worse. Duterte points out that China is already occupying the disputed territory in the South China Sea and no one is willing or able to push them out. China has hired several hundred Chinese fishing boats and their crews as a part-time naval militia to conduct a blockage of bits of land in the South China Sea that the Philippines physically occupies, hoping to block supplies and force the Filipinos to evacuate these outposts so that China can take possession. Again no one with sufficient military power (like the United States) is willing to confront China over these actions and the Philippines is trying to get clarifications over what exactly the mutual defense treaty the U.S. and Philippines have long had actually covers.
This pragmatism has caused problems because Filipino public opinion favors vigorously opposing these moves while the government does not want to offend the Chinese and endanger the growing number of Chinese economic programs in the Philippines. The government is accused of being bought by the Chinese while the government points out that opposing the Chinese claims in the South China Sea and off the Filipino cost is futile because the Chinese are much more powerful militarily and economically. Yet the public opinion continues to oppose the Chinese, especially since none of the Chinese economic benefits have actually come to pass. This leaves the impression that China thinks so little of Filipinos that it can buy compliance with empty promises and more substantial threats. President Duterte is pressuring China to make good on its economic promises and so far is just getting more assurances that good things are coming. This leads critics of the Duterte approach to point out the Chinese track record of promising much and delivering little in all its diplomatic endeavors.
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November 24, 2018: The Philippines, Japan, South Korea and other East Asian nations are complaining to China about the increase in illegal Chinese workers showing up in their territory. These illegals come in as tourists or business visitors and stay behind when their visa expires. China is believed to be deliberately tolerating this as part of some espionage effort...
November 23, 2018: An agreement was signed with China to jointly develop oil and natural gas deposits found in what is technically Filipino territory. China has threatened military action against Filipino moves to develop these deposits by themselves. The same aggressive tactics were used against Vietnam. China and the Philippines also signed 28 other economic agreements, none of them particularly binding on China. In 2016 China signed a similar collection of investment deals which involved China putting $24 billion worth of economic investments into the Philippines. So far only $62 million has arrived, for an irrigation project. That’s less than one quarter of one percent. Most Filipinos are not impressed, at least not in a positive fashion.
There's more at the link.
It's a very well-known strategy. In Africa, we'd say: "How do you eat an elephant? Mouthful by mouthful." The more mouthfuls China eats, a little bit at a time, the more it swallows of the entire elephant - the South China Sea and neighboring waters. Its clearly stated objective is to exercise total control over the area, and keep other nations out.
The Philippines can't stand up to that sort of pressure. It doesn't have the economic or military strength to do so. The USA has no territory in the area, so it's reluctant to commit American lives in a possible military conflict with China over the issue. This has to worry Taiwan, too. Its agreements with the USA are effectively so much toilet paper now. China's military strength has become so great that the US simply could not prevent a forcible 'reunification' of the island with the mainland. Promises to the contrary are meaningless in the light of current world geopolitical realities.
This does not bode well for the future. If China is allowed to get away with such behavior, it will be emboldened to do more of the same in future . . . but who's to stop it? I certainly don't think the issue is worth American lives. That, of course, is what the Chinese are counting on - and they think dominance of the South China Sea is worth Chinese lives, if necessary.