I suspect China will be waiting for NATO to fall apart to do anything. If NATO doesn't fracture (i.e. enough less syphilitic relics from Reagan's GOP remember Ruskies aren't our friends), China isn't going to risk its place in the global economy, because losing access to European AND North American markets would probably mean a return to a planned economy.
I hope to fuck that doesn't happen. The US does not have a near peer in Asia. If there's sabre-rattling, we can park enough carrier groups in the Pacific to make an issue of anything China wants to do. We CAN'T stop China from sacking Taiwan, but the ROC will absolutely go scorched Earth before it gives the PRC anything at all and they'd never get enough troops ashore for long enough to entrench before the US and whatever pathetic SE Asian regional coalition showed up. It would be a meat grinder for Chinese marines and unless somebody wants to start slinging nukes, it would be complete insanity to directly attack any part of a CSG.
China hasn't had to fight anybody remotely capable of big-boy warfare in its history. It squabbles over borders with India and Pakistan sometimes, killing tens of people on either side every year. It keeps talking about next generation carriers and hypersonic missiles and maybe it has a drone doctrine in advance of the Pentagon thinks it does, but at the end of the day, it's not going to be able to keep anything in the air and can guarantee the safety of anything other than its subs at sea if the US gets involved. If they're fixated on that island, fine, it'll be rubble in no time, but congratulations on setting the global economy back a decade over a point of pride. Unless they want to make it all nuclear, or they're willing to bribe Trump off to an unfathomable degree, it's not a winning scenario for the PRC, even if the US were to go it alone over there.