US obviously not willing to fight over South China Sea, Taiwan

Mark Valencia (writing at the Diplomat) finally admitted that it is s finally clear that the United States is not willing to confront China over the South China Sea.
China continues to militarize the South China Sea features it occupies and to assert its questionable maritime claims versus other claimants. U.S. rhetoric has sharply criticized China’s behavior and implied dire consequences if it persists. But China has persisted and it has become clear that America is not going to rescue the other claimants from perceived intimidation and coercion. The realization that the United States will not be coming to the rescue is belatedly beginning to sink in throughout the region and misplaced hope is being replaced by bitter disappointment and even despair. However to seasoned observers, this development was not a surprise.
Vietnam and the international supporters of its position are the latest to come to this realization.

Very Obvious since 2015
Indications that the United States was unlikely to militarily support even an ally like the Philippines regarding the South China Sea disputes surfaced when China muscled its way to control of the Philippines-claimed Scarborough Shoal. The Philippines had hoped that the United States would intervene on its behalf, but it was not to be.
In August 2015, current Philippine President Rodrigo Duterte’s blunt pragmatic assessment that “America would never die for us” — a reference to U.S. vagueness on whether or not it would come to the aid of the Philippine military in a conflict in the Spratlys or Scarborough Shoal. Duerte has also stated that “China is now in power and they have military superiority in the region.”
Analysts like Australia’s Hugh White, who argues that Washington has shown “no appetite for engaging in a confrontation with China” in China’s own backyard where the U.S. might take heavy losses and not win quickly.
US Core interests not at stake over South China Sea or Taiwan
In a 2017 article in Foreign Affairs, veteran policy analysts Robert Manning and James Przystup conclude that “the reality is that US core interests are not really at stake [in the South China Sea] and China knows it.
People in the region watching Beijing stake claims to disputed South China Sea rocks and shoals have no illusions that China is being deterred by the United States. They have come to understand the reality of an asymmetry of respective Chinese and U.S. geopolitical interests. Beijing’s interest in the South China Sea is political and strategic in nature. Island building is aimed at asserting sovereignty to reverse the “century of humiliation,” which has become a key to legitimacy for the Chinese Communist Party. Strategically, China is pushing out its defense perimeter and enhancing China’s maritime sway in the region.
But for the United States, the South China Sea is just one part of the larger, complex U.S.-China relationship. Former President Barack Obama’s policy priorities for China were the Paris climate change accords and the Iran nuclear deal; Donald Trump’s policy priorities for China are North Korea and trade.

Nextbigfuture reviews who the US will and will not fight
The US will beat up on Vietnam, North Korea without nuclear weapons, Iraq (twice), Syria, Libya and Afghanistan.
The US will think about and may actually have a war with Iran and North Korea with a few nuclear weapons. However, only if there is an aggressive President like Trump and not if there was a passive President like Obama.
The US would only fight a China or even a Russia if directly attacked the USA, a major European or NATO ally. It would be automatic if it was an attack on US or friendly territory with over 200 casualties.
In the 1990s and before China was far weaker. The US was willing to make China backoff Taiwan with a small show of force. China has moved up in power.