[0] clarified to be within TW relations act, i.e. help TW defend itself, aka, basically no boots on ground in Ukraine tier of promise. US has even less capability of defending TW within first island chain then it does Ukraine. The idea of course is there will be some sort of naval contest, but that will likely change once PRC expands nuclear arsenal to the point of "That’s a world war when Americans and China start shooting at one another".