But given how messed up & fragmented the EU military is if the US stops military support for Taiwan china will likely directly declare War and Attack. (To be precise there is no EU military, just that of all members which makes it fragmented and in many cases is their military isn't in the best condition. Also China wouldn't declare War as it doesn't recognizance Taiwan, i.e. they would instead "use military force to attack rebels and terrorists" or something like that).