The US has long tried to avoid directly needling China over Taiwan, by taking a position of ambiguity as to whether the US would immediately go to war to prevent a Chinese takeover of the island. President Biden has done away with that ambiguity now, however, saying he absolutely would go to war over Taiwan.
Biden summed up his statement with “I don’t want a cold war with China. I just want China to understand that we’re not going to step back, that we’re not going to change any of our views.”
That’s an unfortunately common US stance to take, not wanting a war but ruling out any discussions or flexibility to avoid one. While the US was nominally worried China would blunder without such a stance, the greater risk is the US blundering into a war through sheer stubbornness.
Biden has been pushed to take this stance by anti-China hawks. At this point it’s not particularly necessary, as Taiwan is currently such an important trade partner for the whole region that such a war would be damaging to all sides.
China and Taiwan are going through some tensions lately, with China accusing Taiwan of behaving provocatively in acting as though they are autonomous.
The US position on Taiwan is bizarre, and has been for decades. After initially recognizing Taiwan as rightful government of all of China, they reversed and recognized the PRC.
Officially, then, the US doesn’t recognize Taiwan at all anymore, and has no embassy or diplomatic relations, apart from some work-alike “unofficial” facilities run by the State Department.
On top of maintaining an “unofficial” relationship, US law also commits the US to massive arms sales to Taiwan, which have been very large in recent years. Those arms sales similarly fuel tensions with China.
Biden’s statement doesn’t practically change any of that, though the threat of war clearly puts the US down a path of worse relations with China.