Comment by Green_man

Territorial disputes are a problem for NATO membership, especially wrt article 5. Even if Taiwan gave up any claims to the Chinese mainland or other disputed territories, China's claims of sovereignty of the island could justifiably be enough to deny membership. On top of that, NATO is explicitly a European organization, with no member countries outside the European area besides USA and Canada. https://www.nato.int/cps/en/natohq/official_texts_24733.htm